SDILEGE ADVANCE TABLET

Mechanism of action

Cyanocobalamin serves as a cofactor for methionine synthase and L-methylmalonyl-CoA mutase enzymes. Methionine synthase is essential for the synthesis of purines and pyrimidines that form DNA. L-methylmalonyl-CoA mutase is involved in the degradation of propionate, crucial for fat and protein metabolism. The lack of vitamin B12 results in the accumulation of methylmalonyl CoA, contributing to neurological manifestations. Additionally, it is vital for the synthesis of methionine from homocysteine, and its deficiency can lead to functional folate deficiency, which impacts red blood cell formation.

Pharmacodynamics

Cyanocobalamin corrects vitamin B12 deficiency and alleviates symptoms and laboratory abnormalities associated with pernicious anemia, such as megaloblastic indices, gastrointestinal lesions, and neurological damage. It is essential for growth, cell reproduction, hematopoiesis, nucleoprotein, and myelin synthesis. The drug significantly impacts fat and carbohydrate metabolism, as well as protein synthesis. Rapidly dividing cells, such as those in the bone marrow, have a high demand for vitamin B12. Parenteral administration of cyanocobalamin can quickly reverse the anemia and gastrointestinal symptoms of vitamin B12 deficiency, while also preventing the progression of related neurological damage.

Pharmacokinetics

Cyanocobalamin is absorbed in the intestine, primarily in the ileum, via specific transport mechanisms that may be impaired in individuals with intrinsic factor deficiency (as seen in pernicious anemia). Once absorbed, it is widely distributed in body tissues, with significant concentrations found in the liver, kidneys, and heart. The vitamin is stored in the liver, where it can be released into circulation as needed. Cyanocobalamin undergoes conversion to its active forms, methylcobalamin and adenosylcobalamin, which are utilized in various metabolic processes. The elimination half-life is variable, but it is generally excreted via urine as metabolites

Adverse effects

• Abdominal distension
• Decreased appetite
• Flatulence
• Nausea

Interactions

• Folic acid may interact with cyanocobalamin, especially in cases of megaloblastic anemia caused by folate deficiency.

Precautions

• Should not be given alone for pernicious anemia.
• Use caution in patients with Leber's disease, as it may worsen optic atrophy.

Pregnancy

Cyanocobalamin is essential during pregnancy as it helps prevent neural tube defects. It is advised that females of childbearing potential take 5 mg of folic acid daily before conception and throughout pregnancy.

Breast-feeding

Cyanocobalamin is generally considered safe during breastfeeding, but it is advised to monitor the infant for any adverse effects.

Storage

Store in a cool, dry place, away from direct sunlight. Protect from moisture.

Formulations

• Tablet: 1000 micrograms
• Tablet: 500 micrograms
• Tablet: 100 micrograms
• Oral solution: 50 micrograms per ml
• Solution for injection: 1000 micrograms per ml

Indications

• Vitamin B6 deficiency
• Isoniazid-induced neuropathy (prophylaxis and treatment)
• Idiopathic sideroblastic anaemia
• Prevention of penicillamine-induced neuropathy in Wilson's disease
• Metabolic diseases such as cystathioninuria and homocystinuria
• Premenstrual syndrome

Mechanism of action

Pyridoxine hydrochloride is converted in the body to pyridoxal phosphate, which is the active form of vitamin B6. It serves as a cofactor for more than 100 enzymatic reactions, particularly those involved in the metabolism of amino acids, the synthesis of neurotransmitters (such as serotonin, dopamine, and gamma-aminobutyric acid), and the production of hemoglobin. Its role in neurotransmitter synthesis makes it crucial for normal brain function and mood regulation.

Pharmacodynamics

Pyridoxine hydrochloride exerts its effects by facilitating the conversion of amino acids into neurotransmitters and is involved in the synthesis of heme. It impacts the metabolism of tryptophan to serotonin and is essential for the production of norepinephrine and gamma-aminobutyric acid, which are vital for proper neurological function. Deficiency of vitamin B6 can lead to neurological symptoms, including peripheral neuropathy and cognitive disturbances.

Pharmacokinetics

Pyridoxine hydrochloride is readily absorbed from the gastrointestinal tract. It is primarily metabolized in the liver, where it is converted to its active form, pyridoxal phosphate. The elimination half-life of pyridoxine is approximately 15-20 days, and it is excreted primarily through the urine. Renal impairment may affect the metabolism and excretion of pyridoxine, necessitating dose adjustments.

Contra-indications

• Hyperkalaemia
• Severe liver damage

Adverse effects

• Peripheral neuritis
• Hepatitis
• Hypoglycaemia
• Urine discolouration

Interactions

• Potassium aminobenzoate
• Isoniazid

Precautions

• Caution in renal impairment (increased risk of hyperkalaemia)
• Interrupt treatment during periods of low food intake (such as fasting, anorexia, and nausea) to reduce risk of hypoglycaemia
• Monitor liver function tests monthly during high-dose therapy

Pregnancy

Manufacturer advises avoiding use in pregnancy due to potential risk of birth defects; however, no adverse effects have been reported at normal dietary levels.

Breast-feeding

Theoretical risk of toxicity in infants if mothers take large doses.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Pyridoxine hydrochloride 10 mg tablets
• Pyridoxine hydrochloride 20 mg tablets
• Pyridoxine hydrochloride 50 mg tablets
• Pyridoxine hydrochloride oral solution 20 mg per 1 ml

Indications

• Vitamin C deficiency
• Scurvy
• Adjunct therapy in iron overload conditions

Dosage

Children: Child 1 month–3 years: 125–250 mg daily in 1–2 divided doses; Child 4–11 years: 250–500 mg daily in 1–2 divided doses; Child 12–17 years: 0.5–1 g daily in 1–2 divided doses.

Adults: 500 mg daily, taken in 1-2 divided doses, depending on the clinical condition and dietary needs.

Mechanism of action

Ascorbic acid functions primarily as a reducing agent, facilitating enzymatic reactions in the body, including the hydroxylation of proline and lysine in collagen synthesis. It also plays a role in the absorption of iron from the gastrointestinal tract and enhances the immune response.

Pharmacodynamics

Ascorbic acid is crucial for the maintenance of connective tissue and is involved in the metabolism of several amino acids. Its antioxidant properties help to mitigate oxidative stress and may play a role in reducing the risk of chronic diseases.

Pharmacokinetics

Ascorbic acid is absorbed in the intestines and is widely distributed throughout the body. The renal clearance of ascorbic acid is dose-dependent, with higher doses leading to increased excretion. The half-life varies but is generally around 15 to 30 minutes in healthy individuals, with tissue saturation levels influencing its retention.

Contra-indications

• Hypercalcaemia
• Hyperoxaluria
• Patients with cardiac dysfunction

Adverse effects

• Abdominal pain
• Headache
• Nausea
• Vomiting
• Diarrhoea
• Constipation
• Weight loss
• Polyuria
• Sweating
• Thirst
• Vertigo

Interactions

• Increases risk of cardiovascular adverse effects with iron chelators
• Increases risk of cardiovascular adverse effects with deferiprone
• Increases risk of cardiovascular adverse effects with desferrioxamine

Precautions

• Use with caution in patients with iron overload
• Monitor for symptoms of overdose

Pregnancy

High doses teratogenic in animals but therapeutic doses unlikely to be harmful.

Storage

Store in a cool, dry place away from direct sunlight.

Formulations

• Ascorbic acid 50 mg tablets
• Ascorbic acid 100 mg tablets
• Ascorbic acid 200 mg tablets
• Ascorbic acid 250 mg tablets
• Ascorbic acid 500 mg capsules

Indications

• Selenium deficiency
• Supportive therapy in conditions requiring antioxidant support
• Potential adjunct in cancer prevention strategies

Dosage

Children: Refer to BNF for Children for specific dosing information.

Adults: Initially 100–500 micrograms daily, adjusted according to response and serum levels.

Mechanism of action

Selenium is metabolized to selenophosphate and selenocysteine, which are essential for the synthesis of selenoproteins. This process involves the incorporation of selenium into proteins through a specialized tRNA that recognizes the RNA sequence UGA, which is facilitated by SECIS structures and SBP-2 proteins. Key selenoproteins, like glutathione peroxidases, help protect cells from oxidative damage, thus playing a significant role in reducing the risk of diseases such as atherosclerosis and certain cancers.

Pharmacodynamics

Selenium is incorporated into various selenoproteins that perform essential functions, including antioxidant activity, redox balance, and regulation of thyroid hormones. Its role in antioxidant defense mechanisms is particularly important for protecting cells against reactive oxygen species (ROS). Selenium supplementation has been linked to improved immune function and potential cancer prevention.

Pharmacokinetics

Selenium is absorbed through the gastrointestinal tract, and its bioavailability can vary based on the source and form of selenium. Once absorbed, it is distributed to various tissues, where it is incorporated into selenoproteins. Selenium is primarily excreted through urine, and its half-life can depend on dietary intake and individual metabolism. Selenium status can be assessed through blood levels of selenoproteins and selenium itself.

Adverse effects

• Nausea
• Anaemia
• Aplastic anaemia
• Skin reactions
• Gastrointestinal disorders

Precautions

• Selenium supplementation should not be given unless there is good evidence of deficiency.
• Use caution in patients with a history of hypersensitivity to selenium or its compounds.

Pregnancy

Limited information is available regarding selenium supplementation during pregnancy. Consult specialist sources for guidance.

Breast-feeding

Limited information is available; the effect of selenium on copper levels in milk is conflicting, and its impact on the infant is unknown.

Storage

After opening, store in a refrigerator (2–8°C).

Formulations

• Tablets (e.g., L-Selenomethionine 200 micrograms, SelenoPrecise 100 micrograms)
• Capsules (e.g., Trientine dihydrochloride 250 mg)
• Injection solutions (e.g., Sodium selenite 50 micrograms per 1 ml)

Indications

• Hypertension
• Benign prostatic hyperplasia
• Urinary retention related to prostate enlargement

Dosage

Children: Refer to the BNF for Children for appropriate dosing guidelines in the paediatric population.

Adults: Refer to the BNF for specific dosing recommendations based on individual clinical scenarios.

Mechanism of action

Alpha acts by selectively blocking alpha-1 adrenergic receptors, which are responsible for mediating vasoconstriction in blood vessels. By inhibiting these receptors, alpha promotes vasodilation, leading to a decrease in peripheral vascular resistance and subsequently lowering blood pressure. Additionally, this action can help alleviate urinary symptoms associated with an enlarged prostate.

Pharmacodynamics

The pharmacodynamics of alpha involve its competitive antagonism at alpha-1 adrenergic receptors, resulting in decreased vasoconstriction and increased blood flow. This mechanism is beneficial in conditions characterized by high blood pressure and urinary retention due to prostatic enlargement. The onset of action typically occurs within hours, with peak effects observed within a few days of consistent dosing.

Pharmacokinetics

Alpha is absorbed well from the gastrointestinal tract, with peak plasma concentrations achieved within 1-3 hours post-administration. The drug undergoes hepatic metabolism, primarily via cytochrome P450 enzymes, resulting in active and inactive metabolites. The elimination half-life varies, but it generally is around 6-12 hours, allowing for once-daily dosing in many cases. Renal excretion is a significant route for its metabolites, necessitating caution in patients with renal impairment.

Interactions

• maois, irreversible + alpha blockers: Severe (increases effects)
• ribociclib + alpha blockers: Severe (increases exposure)
• cobicistat + alpha blockers: Moderate (increases exposure)
• idelalisib + alpha blockers: Moderate (increases exposure)
• dronedarone + alpha blockers: Unknown (increases exposure)
• antifungals, azoles + alpha blockers: Unknown (increases exposure)
• crizotinib + alpha blockers: Unknown (increases exposure)
• imatinib + alpha blockers: Unknown (increases exposure)
• letermovir + alpha blockers: Unknown (increases exposure)
• clarithromycin + alpha blockers: Unknown (increases exposure)

Indications

• Osteoarthritis
• Rheumatoid arthritis
• Joint pain
• Cartilage repair
• Tissue engineering

Dosage

Children: Dosage for cartilage-related conditions in paediatric patients should be determined by a healthcare professional, taking into account the child's age, weight, and specific clinical situation.

Adults: Dosage for cartilage-related conditions is highly variable and should be determined by a healthcare professional based on individual patient needs and clinical guidelines.

Mechanism of action

Cartilage does not have a specific pharmacological mechanism of action as it is a biological tissue rather than a drug. However, it contributes to joint stability and mobility by reducing friction between bones during movement and absorbing shock. The chondrocytes within cartilage are responsible for maintaining the extracellular matrix, which is essential for the tissue's resilience and function.

Pharmacodynamics

The pharmacodynamics of cartilage is primarily related to its role in joint health and function. It helps to distribute loads across joint surfaces and acts as a cushion to protect bones from impact. The degradation of cartilage, often seen in conditions like osteoarthritis, leads to pain and decreased mobility due to increased friction and bone-on-bone contact. Cartilage also plays a role in the inflammatory response within joints, influencing the severity of conditions like rheumatoid arthritis.

Pharmacokinetics

As cartilage is a biological tissue, it does not have traditional pharmacokinetic properties like absorption, distribution, metabolism, and excretion observed in drugs. However, factors such as age, mechanical stress, and nutritional status can affect the health and maintenance of cartilage. The healing process of cartilage is slow due to its avascular nature, meaning it has limited blood supply and, therefore, a limited capacity for regeneration.

Pregnancy

Data on the safety of cartilage supplements during pregnancy is limited. It is advisable to consult a healthcare provider before use.

Breast-feeding

There is insufficient data on the safety of cartilage supplements during breastfeeding. Consultation with a healthcare provider is recommended.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Indications

• Vitamin D deficiency
• Rickets
• Osteomalacia
• Osteoporosis
• Hypoparathyroidism

Dosage

Adults: The usual adult dose for vitamin D deficiency is 800 to 2000 IU daily, depending on the severity of deficiency and clinical condition. Higher doses may be used under medical supervision.

Mechanism of action

Cholecalciferol is converted to its active forms, 25-hydroxyvitamin D in the liver and 1,25-dihydroxyvitamin D in the kidneys. These metabolites enhance the intestinal absorption of calcium and phosphorus, increase serum calcium levels, and mobilize these minerals from bone. This process is regulated by parathyroid hormone, which influences calcium and phosphate metabolism, particularly in the kidneys.

Pharmacodynamics

The pharmacodynamics of cholecalciferol involve its conversion to active metabolites that play a significant role in calcium and phosphorus homeostasis. The metabolites facilitate intestinal absorption of these minerals, promote bone mineralization, and influence renal reabsorption. The onset of action occurs within 10 to 24 hours following administration, as metabolic activation is required for its biological effects.

Pharmacokinetics

Cholecalciferol is absorbed in the gastrointestinal tract, and its absorption is enhanced by the presence of dietary fats. It is transported in the bloodstream bound to vitamin D-binding protein. Once in the liver, it undergoes hydroxylation to form 25-hydroxyvitamin D, which is further converted in the kidneys to the active form, 1,25-dihydroxyvitamin D. The elimination half-life of cholecalciferol varies, typically spanning several days, and it is primarily excreted in bile and urine.

Adverse effects

• Hypercalcemia
• Hypercalciuria
• Nausea
• Vomiting
• Constipation
• Weakness
• Fatigue

Interactions

• May enhance the effects of thiazide diuretics, leading to increased risk of hypercalcemia
• Anticonvulsants may increase metabolism of vitamin D, leading to reduced effectiveness
• Cholestyramine may reduce absorption of vitamin D

Precautions

• Monitor serum calcium levels in patients with renal impairment
• Caution in patients with a history of hypercalcemia or hyperparathyroidism
• Use with caution in patients taking other medications that affect calcium metabolism

Pregnancy

Cholecalciferol can be used during pregnancy if indicated, as vitamin D is essential for fetal bone development.

Breast-feeding

Cholecalciferol is excreted in breast milk, but is generally considered safe during breastfeeding.

Storage

Store in a cool, dry place, away from light. Keep out of reach of children.

Formulations

• Capsules
• Tablets
• Liquid formulations

Indications

• Skin aging and wrinkle reduction
• Joint pain and osteoarthritis
• Tendon and ligament injuries
• Bone health
• Wound healing

Dosage

Children: Refer to specific product guidelines or consult a healthcare professional for appropriate dosing based on the indication and formulation used.

Adults: Refer to specific product guidelines or consult a healthcare professional for appropriate dosing based on the indication and formulation used.

Mechanism of action

Collagen exerts its effects primarily by providing the necessary amino acids, such as glycine, proline, and hydroxyproline, that are crucial for the synthesis of new collagen in the body. It is thought to stimulate fibroblast proliferation, which leads to increased collagen production and improved tissue repair. Additionally, collagen may enhance the hydration of the skin and improve its elasticity.

Pharmacodynamics

Collagen supplementation may promote the synthesis of new collagen and improve the integrity of the extracellular matrix. This can lead to improved skin hydration, elasticity, and the reduction of wrinkles. In joint health, collagen may help reduce inflammation and pain, contributing to improved mobility and function. The effects can vary based on the source of collagen (bovine, porcine, marine) and the form of administration (powder, liquid, capsules).

Pharmacokinetics

After oral administration, collagen peptides are absorbed in the gastrointestinal tract and enter the bloodstream. They can be transported to various tissues where they may be incorporated into the extracellular matrix. The half-life of collagen peptides is relatively short, and they are metabolized in the liver and other tissues. The bioavailability of collagen can vary based on the formulation and the presence of other dietary components.

Adverse effects

• Allergic reactions
• Skin rash
• Itching
• Gastrointestinal disturbances
• Nausea

Precautions

• Use with caution in individuals with fish allergies if derived from fish sources
• Monitor for allergic reactions

Pregnancy

Collagen is generally considered safe during pregnancy, but consult a healthcare professional before use.

Breast-feeding

Collagen is likely safe during breastfeeding, but consult a healthcare professional before use.

Storage

Store in a cool, dry place, away from direct sunlight. Keep out of reach of children.

Formulations

• Powder
• Capsules
• Liquid

Indications

• Copper deficiency
• Occipital Horn Syndrome
• Menke's disease
• Contraception (via copper IUD)

Dosage

Children: Refer to the BNF for Children for specific dosing information.

Adults: Refer to the relevant clinical guidelines and BNF for specific dosing information.

Mechanism of action

Copper is absorbed from the gastrointestinal tract via high affinity copper uptake proteins and low affinity copper uptake proteins, likely being reduced to the Cu1+ form prior to transport. Inside enterocytes, it binds to the copper transport protein ATOX1, which facilitates its transport to copper transporting ATPase-1 on the Golgi membrane for incorporation into the Golgi apparatus. Once in systemic circulation, copper binds primarily to ceruloplasmin, albumin, and alpha 2-macroglobulin. It acts as a cofactor in a variety of oxidase enzymes and also influences sperm motility when released from copper IUDs, contributing to its contraceptive effect.

Pharmacodynamics

Copper is essential for the activity of many enzymes and plays a vital role in processes such as iron metabolism, neurotransmitter synthesis, and antioxidant defense. Copper ions, particularly when released from intrauterine devices, have been shown to decrease sperm viability, thereby impacting fertility.

Pharmacokinetics

Copper is absorbed from the gut and is predominantly transported in the plasma bound to proteins such as ceruloplasmin and albumin. The absorption efficiency can vary; however, a significant portion of dietary copper is usually absorbed. The body regulates copper levels through hepatic excretion and storage mechanisms, ensuring homeostasis. Excess copper can lead to toxicity, while deficiency results in various health issues.

Pregnancy

Copper is considered essential during pregnancy, but excessive intake should be avoided due to potential toxicity.

Breast-feeding

Copper is excreted in breast milk, and adequate maternal intake is important for infant development.

Storage

Store in a cool, dry place, away from moisture and heat.

Indications

• General wellness support
• Anti-inflammatory effects
• Antioxidant activity
• Digestive aid
• Support for immune function

Dosage

Children: Paediatric dosing should be determined based on the specific extract and its intended use. Consultation with a healthcare provider is recommended for accurate dosing.

Adults: Dosage varies widely depending on the specific extract and formulation. It is essential to follow the manufacturer's instructions or consult a healthcare professional for appropriate dosing.

Mechanism of action

The mechanism of action of herbal extracts can vary significantly based on their constituents. Commonly, they exert their effects through multiple pathways including modulation of neurotransmitter systems, interference with inflammatory processes, or direct antioxidant activity. Some extracts may activate certain receptors or inhibit enzymes related to disease processes.

Pharmacodynamics

The pharmacodynamics of extracts is complex due to the presence of multiple active compounds which can have synergistic or antagonistic effects. These compounds may influence cellular signaling pathways, alter gene expression, or modulate immune response. The overall pharmacological profile is determined by the specific composition of the extract, its concentration, and the biological target it interacts with.

Pharmacokinetics

The pharmacokinetics of extracts involves absorption, distribution, metabolism, and excretion of the active compounds. Generally, herbal extracts are absorbed in the gastrointestinal tract, with bioavailability influenced by factors such as formulation, the presence of food, and individual metabolic differences. Compounds may undergo hepatic metabolism, and elimination can occur through urine or feces, depending on their chemical nature.

Pregnancy

Consult a healthcare professional before use, as the safety of the extract during pregnancy has not been established.

Breast-feeding

Consult a healthcare professional before use, as the safety of the extract during breastfeeding has not been established.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Indications

• Folate deficiency
• Megaloblastic anemia
• Prevention of neural tube defects in pregnancy
• Supplementation in patients on certain medications (e.g., methotrexate)

Dosage

Children: Refer to the BNF for Children for appropriate pa

Adults: Refer to specific guidelines or the BNF for appropriate adult dosing based on the indication.

Mechanism of action

Folate functions as a coenzyme in the conversion of homocysteine to methionine, a process that is vital for DNA synthesis and repair. It is involved in the one-carbon metabolism pathway, where it acts as a carrier of one-carbon units necessary for the synthesis of purines and thymidylate, thus supporting the production of nucleotides and DNA. This mechanism is particularly important in rapidly dividing cells.

Pharmacodynamics

Folate is critical for the formation of red blood cells and the proper functioning of the nervous system. It aids in the production of nucleic acids, which are essential for cell proliferation. Folate deficiency can lead to impaired DNA synthesis, resulting in megaloblastic anemia characterized by the presence of large, immature red blood cells in the bloodstream. Adequate folate levels are also associated with reduced risk of neural tube defects in developing fetuses.

Pharmacokinetics

Folate is absorbed in the proximal part of the small intestine, primarily in the jejunum, and is transported in the bloodstream bound to plasma proteins. It undergoes hepatic metabolism and is stored mainly in the liver. The elimination half-life varies, but dietary folate can be retained in the body for several weeks. Excess folate is excreted through the urine. The bioavailability of folate from food sources is lower compared to synthetic folic acid found in supplements.

Interactions

• folates+fluorouracil: Severe (increases risk of toxicity)
• folates+antiepileptics: Moderate (decreases concentration)
• folates+fosphenytoin: Moderate (decreases concentration)
• folates+phenobarbital: Moderate (decreases concentration)
• folates+phenytoin: Moderate (decreases concentration)
• folates+primidone: Moderate (decreases concentration)
• sulfasalazine+folates: Unknown (decreases absorption)

Pregnancy

Folate is essential for fetal development and is often recommended to prevent neural tube defects.

Breast-feeding

Folate is generally safe during breastfeeding, as it is important for both maternal and infant health.

Storage

Store in a cool, dry place, away from direct sunlight.

Formulations

• Tablets
• Injection

Indications

• Nausea and vomiting (including motion sickness and morning sickness)
• Gastrointestinal discomfort
• Osteoarthritis
• Inflammation
• Cold and flu symptoms

Dosage

Children: Refer to the BNF for Children for appropriate dosing recommendations.

Adults: Refer to established guidelines for specific dosing; typically, doses range from 1 to 3 grams of dried ginger per day.

Mechanism of action

The active components of ginger, particularly gingerols, exert their effects primarily through the inhibition of pro-inflammatory cytokines and enzymes, such as cyclooxygenase and lipoxygenase. This action helps to reduce inflammation and pain. Additionally, ginger enhances gastrointestinal motility and has antiemetic properties, which are beneficial in treating nausea.

Pharmacodynamics

Ginger exhibits anti-inflammatory, antioxidant, and antinausea effects. Its ability to modulate the immune response and inhibit platelet aggregation contributes to its cardiovascular protective effects. The antiemetic properties of ginger are particularly effective in reducing nausea and vomiting associated with motion sickness and chemotherapy.

Pharmacokinetics

Ginger is rapidly absorbed in the gastrointestinal tract, with its active components being metabolized in the liver. The bioavailability of ginger compounds may vary, with gingerols being converted into shogaols during processing or heating. The elimination half-life and specific metabolic pathways have not been extensively studied, but the effects can be observed within 30 minutes to 2 hours after ingestion.

Contra-indications

• Gallstones
• Bleeding disorders
• Allergy to ginger or other plants in the Zingiberaceae family

Adverse effects

• Gastrointestinal disturbances (nausea, diarrhea, heartburn)
• Allergic reactions (skin rash, itching)
• Increased risk of bleeding

Interactions

• Anticoagulants (e.g., warfarin, aspirin)
• Antiplatelet agents
• Certain antihypertensives
• Diabetes medications (may enhance effects)

Precautions

• Use with caution in patients with diabetes, hypertension, or gallbladder disease
• Consult a healthcare provider before use in pregnancy or lactation

Pregnancy

Generally considered safe in food amounts, but high doses should be avoided due to potential effects on uterine contractions.

Breast-feeding

Considered safe in food amounts, but high doses should be avoided.

Storage

Store in a cool, dry place away from direct sunlight.

Formulations

• Dried ginger powder
• Ginger root (fresh)
• Ginger tea
• Ginger extract (liquid or capsule)
• Ginger oil

Indications

• Cognitive decline
• Memory enhancement
• Peripheral vascular disease
• Tinnitus
• Vision problems associated with glaucoma

Dosage

Children: Refer to product-specific guidelines or consult with a healthcare professional for appropriate dosing.

Adults: Refer to product-specific guidelines or consult with a healthcare professional for appropriate dosing.

Mechanism of action

Ginkgo biloba exerts its effects primarily through two mechanisms: first, it enhances blood flow to the brain and other parts of the body by promoting vasodilation, which is mediated by the release of nitric oxide. Second, it possesses antioxidant properties that help to protect cells from oxidative stress by scavenging free radicals and inhibiting lipid peroxidation. This dual action may contribute to its cognitive-enhancing effects and improved peripheral circulation.

Pharmacodynamics

The pharmacodynamics of Ginkgo biloba are characterized by its action on the central nervous system and peripheral vascular system. It may improve memory and cognitive function in individuals with age-related cognitive decline. The flavonoids and terpenoids present in Ginkgo biloba are thought to be responsible for its neuroprotective and vasodilatory effects. Additionally, Ginkgo biloba may have anti-inflammatory properties and modulate neurotransmitter systems, including serotonergic and dopaminergic pathways.

Pharmacokinetics

Ginkgo biloba is absorbed in the gastrointestinal tract, with peak plasma concentrations occurring approximately 1-4 hours after oral administration. The bioavailability of the active constituents, including flavonoids and terpenoids, can be affected by factors such as formulation and dosage. Ginkgo biloba is metabolized in the liver, and its elimination half-life can vary widely depending on the individual and other factors. The metabolites are primarily excreted via the kidneys.

Contra-indications

• Hypersensitivity to Ginkgo biloba or any component of the formulation
• Active bleeding disorders
• Concurrent use of anticoagulants or antiplatelet medications

Adverse effects

• Gastrointestinal upset
• Headache
• Dizziness
• Allergic skin reactions
• Increased risk of bleeding

Interactions

• Anticoagulants such as warfarin may increase the risk of bleeding
• Antiplatelet drugs may have additive effects on bleeding risk
• Certain antidepressants, particularly MAO inhibitors, can interact with Ginkgo biloba
• Seizure medications may be affected, as Ginkgo may lower the seizure threshold

Precautions

• Use with caution in patients with a history of seizures
• Monitor bleeding risk in patients taking blood-thinning medications
• Caution in those with liver or kidney disease
• Discontinue use prior to surgical procedures

Pregnancy

Ginkgo biloba is not recommended during pregnancy due to the potential risk of bleeding and lack of sufficient safety data.

Breast-feeding

Limited data is available; caution is advised as Ginkgo biloba may affect bleeding risk.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Capsules
• Tablets
• Liquid extracts
• Standardized extracts (e.g., EGb 761)

Indications

• Fatigue
• Stress management
• Cognitive enhancement
• Immune support
• General well-being

Dosage

Children: Refer to specific product guidelines, as dosing in children should be determined by a healthcare professional.

Adults: Refer to specific product guidelines, as dosing can vary based on formulation and intended use.

Mechanism of action

Ginseng is thought to exert its effects through several mechanisms, including modulation of the hypothalamic-pituitary-adrenal (HPA) axis, enhancement of antioxidant activity, and regulation of neurotransmitter levels. Ginsenosides, the active compounds in ginseng, may influence cellular signaling pathways, promote neuroprotection, and enhance immune responses.

Pharmacodynamics

The pharmacodynamic effects of ginseng are attributed primarily to its active constituents, ginsenosides, which interact with various receptors and enzymes in the body. These interactions can lead to increased energy metabolism, improved cognitive function, enhanced physical performance, and modulation of the immune system. Ginseng may also exhibit adaptogenic properties, helping the body to maintain homeostasis under stress.

Pharmacokinetics

Ginsenosides undergo extensive metabolism in the body, primarily by the liver. Bioavailability can vary significantly based on the specific ginsenoside and the method of administration. Ginseng is usually administered orally, with effects typically observed within several hours after ingestion. The elimination half-life of ginsenosides can vary based on the specific compound and individual metabolism, with some studies suggesting that effects may persist for several hours to days.

Adverse effects

• Insomnia
• Headache
• Gastrointestinal disturbances
• Nervousness
• Hypertension
• Allergic reactions

Interactions

• May interact with anticoagulants (e.g., warfarin)
• May enhance the effects of caffeine
• May affect insulin levels and blood sugar control
• Potential interaction with immunosuppressants

Precautions

• Use with caution in patients with hypertension
• May cause sleep disturbances; avoid use before bedtime
• Should be used cautiously in patients with diabetes
• Consult a healthcare provider before use in individuals with autoimmune conditions

Pregnancy

Limited data available. Generally not recommended due to potential hormonal effects.

Breast-feeding

Limited data available. Consult a healthcare provider before use.

Storage

Store in a cool, dry place, away from direct sunlight.

Formulations

• Dried root
• Powdered extract
• Capsules
• Tinctures
• Teas

Indications

• Osteoarthritis of the knee
• Viscosupplementation for joint pain
• Dry eye syndrome
• Ocular surgeries (e.g., cataract surgery)
• Wound healing

Dosage

Adults: Refer to specific guidelines or literature for adult dosing recommendations, as they can vary based on

Mechanism of action

Hyaluronate acts by increasing the viscosity and elasticity of synovial fluid in joints, leading to improved lubrication and shock absorption. It binds to water molecules, thus enhancing the hydration of tissues. In the context of osteoarthritis, it helps to restore the normal viscoelastic properties of the joint fluid, which can help alleviate pain and improve joint function. In ocular applications, it serves to lubricate the surface of the eye, aiding in the comfort and healing of the cornea.

Pharmacodynamics

Hyaluronate's pharmacodynamic effects are primarily related to its hydrophilic nature and its ability to form a gel-like consistency when mixed with water. This property allows it to provide mechanical support and cushioning in joints, reducing friction and wear in the articular cartilage. It also plays a role in cell signaling and tissue hydration, influencing cell proliferation and migration in wound healing.

Pharmacokinetics

Hyaluronate is administered via injection or topical application, depending on the indication. After injection into the joint space, it can remain for several weeks, but its half-life is influenced by factors such as the degree of synovial fluid viscosity and the presence of inflammation. Systemic absorption is minimal, and it is primarily metabolized by hyaluronidase enzymes found in various tissues, leading to fragmentation and clearance from the body. In ocular formulations, its retention time on the eye surface can vary based on the formulation and the presence of preservatives.

Contra-indications

• Hypersensitivity to hyaluronate or any component of the formulation
• Infection at the injection site
• Active skin diseases

Adverse effects

• Injection site reactions (pain, swelling, redness)
• Allergic reactions
• Joint effusion
• Increased joint pain
• Headache

Precautions

• Use with caution in patients with bleeding disorders
• Careful consideration in patients with a history of allergic reactions
• Not recommended for intra-articular injection in patients with active infections

Pregnancy

Safety in pregnancy has not been established. Use only if clearly needed and the potential benefits justify the risks.

Breast-feeding

It is not known if hyaluronate is excreted in human milk. Use with caution and only if clearly needed.

Storage

Store at 2-25 degrees Celsius. Protect from light. Do not freeze.

Formulations

• Sodium hyaluronate injection
• Hyaluronic acid gel

Indications

• Diabetic neuropathy
• Oxidative stress-related disorders
• Metabolic syndrome
• Weight management
• Liver health

Dosage

Children: Refer to specific product guidelines, as safety and efficacy in children have not been established.

Adults: Refer to specific product guidelines, as dosages may vary based on the formulation and indication.

Mechanism of action

Lipoic acid acts as a cofactor for mitochondrial enzyme complexes, particularly those involved in the Krebs cycle, enhancing energy production. It also possesses antioxidant properties, neutralizing free radicals and regenerating other antioxidants such as vitamins C and E. Additionally, lipoic acid can modulate various signaling pathways, including those related to insulin sensitivity and inflammation.

Pharmacodynamics

Lipoic acid has a dual role as a coenzyme and an antioxidant. By participating in the decarboxylation of alpha-keto acids, it aids in energy production. Its antioxidant properties contribute to the protection of cells from oxidative stress, which is implicated in various chronic diseases. Lipoic acid can improve insulin sensitivity, making it beneficial in managing glucose metabolism disorders.

Pharmacokinetics

After oral administration, lipoic acid is absorbed in the gastrointestinal tract, with peak plasma concentrations occurring within 30 to 60 minutes. It undergoes hepatic metabolism, primarily via reduction and conjugation, resulting in various metabolites. The elimination half-life is approximately 30 minutes to 2 hours, and it is excreted primarily in urine. The bioavailability of lipoic acid can be affected by food intake.

Adverse effects

• Nausea
• Vomiting
• Abdominal pain
• Skin rash
• Hypoglycemia

Interactions

• May enhance the effects of insulin and other antidiabetic medications
• May interact with heavy metal chelators

Precautions

• Use with caution in patients with diabetes due to the risk of hypoglycemia
• Monitor blood sugar levels in diabetic patients

Pregnancy

Safety during pregnancy has not been established; use only if clearly needed.

Breast-feeding

It is not known whether lipoic acid is excreted in human breast milk; caution is advised.

Storage

Store in a cool, dry place away from light.

Formulations

• Capsules
• Tablets
• Injectable solutions

Indications

• Manganese deficiency
• Bone health and development
• Antioxidant support
• Enzyme cofactor in metabolic processes

Dosage

Children: Refer to the BNF for Children for appropriate dosing recommendations.

Adults: Refer to specific clinical guidelines or the BNF for appropriate dosing recommendations.

Mechanism of action

Manganese serves as a cofactor for several enzymes, including manganese superoxide dismutase (MnSOD), which protects cells from oxidative stress by catalyzing the dismutation of superoxide radicals into oxygen and hydrogen peroxide. It also participates in the activation of enzymes involved in carbohydrate, fat, and protein metabolism.

Pharmacodynamics

Manganese plays a role in various biochemical pathways, particularly in the metabolism of amino acids, cholesterol, glucose, and carbohydrates. It is crucial for bone formation and the maintenance of cartilage. Manganese also aids in the synthesis of glycosyltransferases, which are important for the formation of glycoproteins and proteoglycans.

Pharmacokinetics

Manganese is absorbed primarily in the small intestine, with absorption efficiency influenced by dietary factors and the presence of competing minerals. It is transported in the bloodstream bound to proteins such as alpha-2-macroglobulin and transferrin. Manganese is stored in the liver, pancreas, and bones, and is excreted primarily through bile and to a lesser extent in urine. Its half-life in the human body is not well defined due to its trace nature and variable absorption.

Pregnancy

Manganese is classified as a dietary mineral that is essential for human health, but excessive intake should be avoided during pregnancy as it may affect fetal development.

Breast-feeding

Manganese is present in breast milk, and normal dietary intake is considered safe during breastfeeding. However, excessive supplementation should be avoided.

Storage

Store in a cool, dry place, away from direct light and moisture.

Dosage

Children: As with adult dosing, methane is not used therapeutically in paediatrics, and thus no specific paediatric doses are provided. Refer to clinical guidelines for any relevant applications.

Adults: Methane is not typically administered as a drug in therapeutic contexts. Therefore, specific dosage recommendations for adults do not apply. Consult relevant guidelines or literature for any potential applications.

Mechanism of action

Methane serves as a carbon source in various metabolic processes, particularly in methanogenic archaea and certain bacteria. It participates in biochemical pathways such as methylphosphonate degradation and the oxidation of methane to methanol, facilitating energy production and carbon cycling in anaerobic environments.

Pharmacodynamics

In the context of environmental and biological systems, methane acts as a substrate for methanogenic organisms. These organisms utilize methane to produce energy through anaerobic respiration. The dynamics of methane in the environment are influenced by factors such as temperature, pH, and the presence of other substrates or microorganisms.

Pharmacokinetics

Methane is generally not absorbed in a conventional pharmacokinetic sense as it is primarily a gas. Its distribution and metabolism occur in the environment rather than within a biological system. Methane's clearance from the atmosphere occurs through various processes, including oxidation to carbon dioxide and assimilation by methanotrophic bacteria.

Pregnancy

Methane is not recommended during pregnancy due to potential risks associated with exposure to flammable gases.

Breast-feeding

There is limited information regarding the effects of methane during breastfeeding, exercise caution.

Storage

Store in a cool, dry place away from sources of ignition and incompatible materials.

Indications

• Osteoarthritis
• Joint pain
• Inflammatory conditions
• Skin health
• Muscle recovery

Dosage

Children: Refer to product-specific guidelines, as doses may vary based on formulation and indication.

Adults: Refer to product-specific guidelines, as doses may vary based on formulation and indication.

Mechanism of action

The exact mechanism of action of methylsulfonylmethane is not fully understood. However, it is believed to exert its effects primarily through its anti-inflammatory properties, which may involve the inhibition of pro-inflammatory cytokines and enzymes. Additionally, MSM may enhance the permeability of cell membranes, facilitating the transport of nutrients and the removal of waste products, thereby promoting overall cellular health.

Pharmacodynamics

Methylsulfonylmethane exhibits anti-inflammatory and analgesic properties. It has been shown to modulate the immune response and reduce oxidative stress, which may contribute to its therapeutic effects in conditions characterized by inflammation and pain. The compound has also been associated with improved joint function and reduced symptoms of osteoarthritis in some clinical studies.

Pharmacokinetics

Methylsulfonylmethane is well-absorbed after oral administration, with peak plasma concentrations typically occurring within 1 to 2 hours. It is rapidly distributed throughout the body and is primarily eliminated through the urine. The half-life of MSM is relatively short, leading to the need for multiple doses throughout the day for sustained effects. Its metabolism does not involve extensive hepatic processing, making it generally well-tolerated in various populations.

Adverse effects

• Gastrointestinal disturbances
• Headaches
• Dizziness
• Skin reactions

Precautions

• Use with caution in patients with known allergies
• Monitor for potential gastrointestinal side effects

Pregnancy

There is limited data on the safety of methylsulfonyl during pregnancy. Consult a healthcare provider for risk assessment.

Breast-feeding

Methylsulfonyl is excreted in breast milk. Consult a healthcare provider before use during breastfeeding.

Storage

Store in a cool, dry place, away from direct sunlight.

Indications

• Cardiovascular disease prevention
• Hypertriglyceridemia
• Rheumatoid arthritis
• Inflammatory bowel disease
• Cognitive decline and dementia
• Mood disorders

Dosage

Adults: Dosage varies based on the condition being treated. For general health, a common recommendation is 250-500 mg of combined EPA and DHA

Mechanism of action

Omega fatty acids exert their effects through various mechanisms, including the modulation of inflammatory pathways and the synthesis of specialized pro-resolving mediators. They are incorporated into cell membranes, affecting membrane fluidity and receptor function. Omega-3 fatty acids can also decrease the production of pro-inflammatory eicosanoids and increase anti-inflammatory mediators, promoting a balanced inflammatory response.

Pharmacodynamics

The pharmacodynamics of omega fatty acids involve their role in cellular signaling, gene expression, and lipid metabolism. Omega-3 fatty acids, particularly EPA and DHA, have been shown to influence the resolution of inflammation and enhance endothelial function. They also play a role in neuroprotection and cognitive function, with evidence suggesting that adequate omega-3 intake is associated with reduced risk of neurodegenerative diseases.

Pharmacokinetics

Omega fatty acids are absorbed in the intestine through the action of bile salts and pancreatic enzymes. Once absorbed, they are transported via chylomicrons into the lymphatic system and then into the bloodstream. They are distributed throughout the body, particularly in the brain and heart. The half-life of omega fatty acids can vary, with some studies suggesting an elimination half-life of several days to weeks, depending on the specific fatty acid and individual metabolism. They undergo beta-oxidation for energy production and can be converted into eicosanoids, which mediate various physiological functions.

Adverse effects

• Nausea
• Diarrhea
• Fishy aftertaste
• Allergic reactions
• Increased bleeding risk

Interactions

• Anticoagulants may increase the risk of bleeding when combined with omega-3 fatty acids
• Antihypertensive medications may have additive effects on blood pressure

Precautions

• Use cautiously in patients with bleeding disorders
• Monitor patients on anticoagulants for signs of increased bleeding
• Consider the source of omega-3 fatty acids, as some may contain contaminants

Pregnancy

Generally considered safe when used in recommended amounts, but high doses should be avoided due to potential bleeding risk.

Breast-feeding

Considered safe; omega-3 fatty acids can be beneficial for both mother and infant.

Storage

Store in a cool, dry place, away from light. Refrigeration may be required for some formulations to maintain stability.

Formulations

• Capsules
• Softgels
• Liquid oil
• Fortified foods

Indications

• Vitamin B6 deficiency
• Peripheral neuropathy associated with isoniazid therapy
• Supplementation in specific dietary deficiencies

Dosage

Children: Refer to the BNF for Children for specific paediatric dosing guidance.

Adults: Refer to the BNF for specific dosing details, typically 10-50 mg daily for deficiency.

Mechanism of action

Pyridoxine, mainly in its active form pyridoxal 5'-phosphate, is involved in numerous biochemical reactions, including amino acid metabolism, glycogen breakdown, nucleic acid synthesis, and the production of key neurotransmitters. It aids in the synthesis of hemoglobin and sphingolipids, and its deficiency can impair several physiological processes, including immune response and vascular health.

Pharmacodynamics

Pyridoxine is utilized for the prevention and treatment of vitamin B6 deficiency, particularly in individuals undergoing treatment with isoniazid, which can deplete vitamin B6 levels. It may also have beneficial effects on blood pressure and lipid profiles, as studies have shown it can lower both systolic and diastolic blood pressure, inhibit platelet aggregation, and improve cholesterol levels. Additionally, it plays a role in enhancing immune function and protecting endothelial cells from injury.

Pharmacokinetics

Pyridoxine is rapidly absorbed from the gastrointestinal tract. It is transported to tissues where it is phosphorylated to its active form, pyridoxal 5'-phosphate. The vitamin is primarily excreted in urine as pyridoxine and its metabolites. Its half-life varies depending on the individual’s nutritional status and other factors. Adequate dietary intake is essential for maintaining optimal levels in the body.

Pregnancy

Pyridoxine is generally considered safe during pregnancy. However, high doses should be avoided unless specifically prescribed.

Breast-feeding

Pyridoxine is excreted in breast milk, but at normal dietary levels it is considered safe for breastfeeding mothers.

Storage

Store in a cool, dry place away from direct sunlight. Keep out of reach of children.

Formulations

• Tablets
• Oral solution
• Injectable form

Dosage

Children: Refer to specific formulations and preparations for recommended dosing in children, as it varies widely by plant and intended use.

Adults: Refer to specific formulations and preparations for recommended dosing, as it varies widely by plant and intended use.

Mechanism of action

The mechanism of action varies significantly depending on the specific root being referred to. Many plant roots contain bioactive compounds such as alkaloids, flavonoids, and glycosides, which can modulate various biochemical pathways in the body. For instance, certain roots may inhibit enzymes involved in inflammation or microbial growth, while others may enhance immune responses or modulate neurotransmitter activity.

Pharmacodynamics

Pharmacodynamics will differ based on the specific root and its active compounds. Generally, roots may exhibit anti-inflammatory, analgesic, antimicrobial, or antioxidant effects. The pharmacodynamic profile will also depend on factors such as dosage, preparation method (e.g., decoction, tincture), and the specific condition being treated. For example, some roots may interact with cellular receptors, while others may exert their effects through modulation of gene expression.

Pharmacokinetics

The pharmacokinetics of a root extract will vary with the specific plant. Typically, factors such as absorption, distribution, metabolism, and excretion are influenced by the chemical composition of the root, the method of preparation, and the route of administration. Many active compounds are absorbed in the gastrointestinal tract, metabolized in the liver, and excreted via urine or feces. The bioavailability of these compounds can be affected by their solubility and stability.

Pregnancy

The safety of root during pregnancy has not been established. Consult a healthcare professional before use.

Breast-feeding

It is unknown whether root is excreted in human milk. Caution is advised when administering to nursing mothers.

Storage

Store in a cool, dry place away from direct sunlight and moisture.

Indications

• Anxiety
• Depression
• Skin wounds
• Inflammation
• Aromatherapy for relaxation

Dosage

Children: Refer to relevant guidelines and literature for specific dosing recommendations, as rose extracts vary widely in concentration and formulation.

Adults: Refer to relevant guidelines and literature for specific dosing recommendations, as rose extracts vary widely in concentration and formulation.

Mechanism of action

The essential oil from rose contains various compounds such as phenyl ethanol, geraniol, and citronellol, which may exert their effects through the modulation of neurotransmitter systems. It is believed to influence the central nervous system, promoting relaxation and reducing anxiety. Additionally, rose extracts possess antioxidant properties, which may contribute to their anti-inflammatory effects.

Pharmacodynamics

Rose extracts have been shown to have anxiolytic and antidepressant effects, likely through the enhancement of serotonin and dopamine levels in the brain. The anti-inflammatory properties are attributed to the inhibition of pro-inflammatory cytokines and modulation of immune responses. The antioxidant activity helps protect cells from oxidative stress.

Pharmacokinetics

The pharmacokinetics of rose extracts are not well-documented due to variations in preparation and formulation. However, the constituents are generally absorbed through the skin or mucous membranes when used topically or in aromatherapy. The bioavailability and half-life of specific compounds can vary widely, influenced by factors such as formulation, dosage, and individual metabolism.

Pregnancy

Insufficient data on the safety of rose during pregnancy. Consult healthcare provider before use.

Breast-feeding

Limited information available. Consult healthcare provider before use.

Storage

Store in a cool, dry place away from direct sunlight.

Indications

• Osteoarthritis
• Rheumatoid arthritis
• Cancer
• Cardiovascular diseases
• Skin disorders

Dosage

Children: Refer to specific product guidelines and consult a healthcare provider for appropriate dosing in children.

Adults: Refer to specific product guidelines, as dosages may vary widely depending on the formulation and intended use.

Mechanism of action

The exact mechanism of action of shark cartilage is not fully understood. It is believed to work by inhibiting angiogenesis, the process through which new blood vessels form from pre-existing vessels, which is crucial for tumor growth and metastasis. The compounds within shark cartilage may also modulate immune responses and exhibit anti-inflammatory effects.

Pharmacodynamics

Shark cartilage is thought to exert its effects through various biological pathways, primarily by interacting with the immune system and influencing cellular communication. It may have anti-inflammatory effects that reduce swelling and pain, particularly in joint disorders. Additionally, its potential anti-cancer properties are attributed to its ability to inhibit the growth of blood vessels that supply tumors.

Pharmacokinetics

The pharmacokinetics of shark cartilage have not been well-studied. It is generally consumed as an oral supplement, and its bioavailability may vary depending on the formulation. The components of shark cartilage, including glycosaminoglycans, are likely to be absorbed through the gastrointestinal tract, but the extent of absorption and metabolism remains unclear. Further research is needed to elucidate the pharmacokinetic profile of shark cartilage.

Pregnancy

There is limited data on the safety of shark products during pregnancy. Consult healthcare providers for personalized advice.

Breast-feeding

Limited data on the safety of shark products during breastfeeding. Consult healthcare providers for personalized advice.

Storage

Store in a cool, dry place away from direct sunlight. Ensure proper sealing to maintain freshness.

Mechanism of action

Vitamin B12 serves as a cofactor for _methionine synthase_ and _L-methylmalonyl-CoA mutase_ enzymes. Methionine synthase is essential for the synthesis of purines and pyrimidines that form DNA. L-methylmalonyl-CoA mutase converts L-methylmalonyl-CoA to _succinyl-CoA_ in the degradation of propionate, an important reaction required for both fat and protein metabolism. It is a lack of vitamin B12 cofactor in the above reaction and the resulting accumulation of methylmalonyl CoA that is believed to be responsible for the neurological manifestations of B12 deficiency. Succinyl-CoA is also necessary for the synthesis of hemoglobin. In tissues, vitamin B12 is required for the synthesis of _methionine_ from homocysteine. Methionine is required for the formation of S-adenosylmethionine, a methyl donor for nearly 100 substrates, comprised of DNA, RNA, hormones, proteins, as well as lipids. Without vitamin B12, tetrahydrofolate cannot be regenerated from 5-methyltetrahydrofolate, and this can lead to functional folate deficiency,. This reaction is dependent on methylcobalamin (vitamin B12) as a co-factor and is also dependent on folate, in which the methyl group of methyltetrahydrofolate is transferred to homocysteine to form _methionine_ and _tetrahydrofolate_. Vitamin B12 incorporates into circulating folic acid into growing red blood cells; retaining the folate in these cells. A deficiency of vitamin B12 and the interruption of this reaction leads to the development of megaloblastic anemia.

Pharmacodynamics

**General effects** Cyanocobalamin corrects vitamin B12 deficiency and improves the symptoms and laboratory abnormalities associated with pernicious anemia (megaloblastic indices, gastrointestinal lesions, and neurologic damage). This drug aids in growth, cell reproduction, hematopoiesis, nucleoprotein, and myelin synthesis. It also plays an important role in fat metabolism, carbohydrate metabolism, as well as protein synthesis. Cells that undergo rapid division (for example, epithelial cells, bone marrow, and myeloid cells) have a high demand for vitamin B12. **Parenteral cyanocobalamin effects** The parenteral administration of vitamin B12 rapidly and completely reverses the megaloblastic anemia and gastrointestinal symptoms of vitamin B12 deficiency. Rapid parenteral administration of vitamin B12 in deficiency related neurological damage prevents the progression of this condition. **Nasal spray effects** In 24 vitamin B12 deficient patients who were already stabilized on intramuscular (IM) vitamin B12 therapy, single daily doses of intranasal cyanocobalamin for 8 weeks lead to serum vitamin B12 concentrations that were within the target therapeutic range (>200 ng/L).

Mechanism of action

Selenium is first metabolized to selenophosphate and selenocysteine. Selenium incorporation is genetically encoded through the RNA sequence UGA. This sequence is recognized by RNA ste loop structures called selenocysteine inserting sequences (SECIS). These structures require the binding of SECIS binding proteins (SBP-2) to recognize selenocystiene. The specialized tRNA is first bound to a serine residue which is then enzymatically processed to a selylcysteyl-tRNA by selenocystiene sythase using selenophosphate as a selenium donor. Other unidentified proteins are required as part of the binding of this tRNA to the ribosome. Selenoproteins appear to be necessary for life as mice with the specialized tRNA gene knocked out exhibited early embryonic lethality. The most important selenoproteins seem to be the glutathione peroxidases and thioredoxin reductases which are part of the body's defenses againts reactive oxygen species (ROS). The importance of selenium in these anti-oxidant proteins has been implicated in the reduction of atherosclerosis by preventing the oxidation of low density lipoprotein. Selenium supplementation is also being investigated in the prevention of cancer and has been suggested to be beneficial to immune function. Converging data from epidemiological, ecological, and clinical studies have shown that selenium (Se) can decrease the risk for some types of human cancers. Induction of apoptosis is considered an important cellular event that can account for the cancer preventive effects of Se. Prior to occurrence of apoptosis, Se compounds alter the expression and/or activities of signaling molecules, mitochondria-associated factors, transcriptional factors, tumor suppressor genes, and cellular reduced glutathione. Mechanistic studies have demonstrated that the methylselenol metabolite pool has many desirable attributes of chemoprevention, whereas the hydrogen selenide pool with excess of selenoprotein synthesis can lead to DNA single-strand breaks. To elucidate the effects of Se on cytotoxic events, it should be remembered that the chemical forms and the dose of Se, and the experimental system used, are determinants of its biological activities. This mini-review focuses on elucidation of the molecular mechanisms of cancer prevention by Se with the apoptotic approach. /Selenium/ Selenium status can also influence thyroid hormone function via the deiodinase enzymes. Selenium is a critical component of the deiodinase enzymes, including iodothyronine 5'-deiodinases, which convert the prohormone thyroxine (T4) to the active circulating form, triiodothyronine (T3). Selenium is also a component of GPX, the main enzyme responsible for protecting thyroid cells against oxidative damage. GPX is involved in the detoxification of hydrogen peroxide, which is produced in the thyroid during the conversion of T4 to T3. /Selenium/ Selenium readily substitutes for sulfur in biomolecules and in many biochemical reactions, especially when the concentration of selenium is high and the concentration of sulfur is low in the organism. Inactivation of the sulfhydryl enzymes necessary for oxidative reactions in cellular respiration, through effects on mitochondrial and microsomal electron transport, might contribute to acute selenium toxicity. Selenium may have a role in hepatic heme metabolism that is related to GPX or lipid peroxidation. Selenocysteine is specifically found in some proteins (e.g., glutathione peroxidase); selenomethionine appears to randomly substitute for methionine in protein synthesis. This appears to be an additional mechanism for intermediate- or chronic-duration toxicity. Skin, hair, and nail damage are significant indicators of chronic selenium overexposure. The mechanism causing these integumentary effects is unclear, but could be related to the high selenium concentrations in these tissues as a consequence of the substitution of selenium for sulfur in certain amino acids, including the disulfide bridges that pr

Pharmacodynamics

Selenium is incorporated into many different selenoproteins which serve various functions throughout the body.

Mechanism of action

Most individuals naturally generate adequate amounts of vitamin D through ordinary dietary intake of vitamin D (in some foods like eggs, fish, and cheese) and natural photochemical conversion of the vitamin D3 precursor 7-dehydrocholesterol in the skin via exposure to sunlight. Conversely, vitamin D deficiency can often occur from a combination of insufficient exposure to sunlight, inadequate dietary intake of vitamin D, genetic defects with endogenous vitamin D receptor, or even severe liver or kidney disease. Such deficiency is known for resulting in conditions like rickets or osteomalacia, all of which reflect inadequate mineralization of bone, enhanced compensatory skeletal demineralization, resultant decreased calcium ion blood concentrations, and increases in the production and secretion of parathyroid hormone. Increases in parathyroid hormone stimulate the mobilization of skeletal calcium and the renal excretion of phosphorus. This enhanced mobilization of skeletal calcium leads towards porotic bone conditions. Ordinarily, while vitamin D3 is made naturally via photochemical processes in the skin, both itself and vitamin D2 can be found in various food and pharmaceutical sources as dietary supplements. The principal biological function of vitamin D is the maintenance of normal levels of serum calcium and phosphorus in the bloodstream by enhancing the efficacy of the small intestine to absorb these minerals from the diet. At the liver, vitamin D3 or D2 is hydroxylated to 25-hydroxyvitamin D and then finally to the primary active metabolite 1,25-dihydroxyvitamin D in the kidney via further hydroxylation. This final metabolite binds to endogenous vitamin d receptors, which results in a variety of regulatory roles - including maintaining calcium balance, the regulation of parathyroid hormone, the promotion of the renal reabsorption of calcium, increased intestinal absorption of calcium and phosphorus, and increased calcium and phosphorus mobilization of calcium and phosphorus from bone to plasma to maintain balanced levels of each in bone and the plasma. In particular, calcitriol interacts with vitamin D receptors in the small intestine to enhance the efficiency of intestinal calcium and phosphorous absorption from about 10-15% to 30-40% and 60% increased to 80%, respectively. Furthermore, calcitriol binds with vitamin D receptors in osteoblasts to stimulate a receptor activator of nuclear factor kB ligand (or RANKL) which subsequently interacts with receptor activator of nuclear factor kB (NFkB) on immature preosteoclasts, causing them to become mature bone-resorbing osteoclasts. Such mature osteoclasts ultimately function in removing calcium and phosphorus from bone to maintain blood calcium and phosphorus levels. Moreover, calcitriol also stimulates calcium reabsorption from the glomerular filtrate in the kidneys. Additionally, it is believed that when calcitriol binds with nuclear vitamin D receptors, that this bound complex itself binds to retinoic acid X receptor (RXR) to generate a heterodimeric complex that consequently binds to specific nucleotide sequences in the DNA called vitamin D response elements. When bound, various transcription factors attach to this complex, resulting in either up or down-regulation of the associated gene's activity. It is thought that there may be as much as 200 to 2000 genes that possess vitamin D response elements or that are influenced indirectly to control a multitude of genes across the genome. It is in this way that cholecalciferol is believed to function in regulating gene transcription associated with cancer risk, autoimmune disorders, and cardiovascular disease linked to vitamin D deficiency. In fact, there has been some research to suggest calcitriol may also be able to prevent malignancies by inducing cellular maturation and inducing apoptosis and inhibiting angiogenesis, exhibit anti-inflammatory effects by inhibiting foam cell formation and promoting angiogenesis in en

Pharmacodynamics

The in vivo synthesis of the predominant two biologically active metabolites of vitamin D occurs in two steps. The first hydroxylation of vitamin D3 cholecalciferol (or D2) occurs in the liver to yield 25-hydroxyvitamin D while the second hydroxylation happens in the kidneys to give 1, 25-dihydroxyvitamin D. These vitamin D metabolites subsequently facilitate the active absorption of calcium and phosphorus in the small intestine, serving to increase serum calcium and phosphate levels sufficiently to allow bone mineralization. Conversely, these vitamin D metabolites also assist in mobilizing calcium and phosphate from bone and likely increase the reabsorption of calcium and perhaps also of phosphate via the renal tubules. There exists a period of 10 to 24 hours between the administration of cholecalciferol and the initiation of its action in the body due to the necessity of synthesis of the active vitamin D metabolites in the liver and kidneys. It is parathyroid hormone that is responsible for the regulation of such metabolism at the level of the kidneys.

Mechanism of action

Copper is absorbed from the gut via high affinity copper uptake protein and likely through low affinity copper uptake protein and natural resistance-associated macrophage protein-2. It is believed that copper is reduced to the Cu1+ form prior to transport. Once inside the enterocyte, it is bound to copper transport protein ATOX1 which shuttles the ion to copper transporting ATPase-1 on the golgi membrane which take up copper into the golgi apparatus. Once copper has been secreted by enterocytes into the systemic circulation it remain largely bound by ceruloplasmin (65-90%), albumin (18%), and alpha 2-macroglobulin (12%). Copper is an essential element in the body and is incorporated into many oxidase enzymes as a cofactor. It is also a component of zinc/copper super oxide dismutase, giving it an anti-oxidant role. Copper defiency occurs in Occipital Horn Syndrome and Menke's disease both of which are associated with impaired development of connective tissue due to the lack of copper to act as a cofactor in protein-lysine-6-oxidase. Menke's disease is also associated with progressive neurological impairment leading to death in infancy. The precise mechanisms of the effects of copper deficiency are vague due to the wide range of enzymes which use the ion as a cofactor. Copper appears to reduce the viabilty and motility of spermatozoa. This reduces the likelihood of fertilization with a copper IUD, producing copper's contraceptive effect. The exact mechanism of copper's effect on sperm are unknown. The reason for the less severe reaction when the foreign body is at a distance from the retina has been proposed to be ... that near the retina & its blood vessels there is greater oxygen tension than at a distance, which causes metallic copper to oxidize to toxic copper compounds more rapidly close to or in contact with the retina than at a distance. Furthermore, the abscess formation that is characteristic of copper undergoing oxidation close to the retina & choroiod can be attributed to attraction of polymorphonuclear leukocytes from these nearby vascular tissues, which become heavily infiltrated. Liquefaction & disorganization of the vitreous body has been explained on the basis of copper catalysis of oxidation of ascorbic acid, leading to depolymerization of the hyaluronic acid of the vitreous humor. Changes in protein & hexosamine content have also been related to decrease in viscosity of the vitreous humor. Increased content of amino acids in the vitreous humor has been consistent with proteolysis of the vitreous body, but decreased concentration in the aqueous humor has suggested suppression of secretion of amino acids by the ciliary body under the influence of copper.

Pharmacodynamics

Copper is incorporated into many enzymes throughout the body as an essential part of their function. Copper ions are known to reduce fertility when released from copper-containing IUDs.

Mechanism of action

Vitamin B6 is the collective term for a group of three related compounds, pyridoxine (PN), pyridoxal (PL) and pyridoxamine (PM), and their phosphorylated derivatives, pyridoxine 5'-phosphate (PNP), pyridoxal 5'-phosphate (PLP) and pyridoxamine 5'-phosphate (PMP). Although all six of these compounds should technically be referred to as vitamin B6, the term vitamin B6 is commonly used interchangeably with just one of them, pyridoxine. Vitamin B6, principally in its biologically active coenzyme form pyridoxal 5'-phosphate, is involved in a wide range of biochemical reactions, including the metabolism of amino acids and glycogen, the synthesis of nucleic acids, hemogloblin, sphingomyelin and other sphingolipids, and the synthesis of the neurotransmitters serotonin, dopamine, norepinephrine and gamma-aminobutyric acid (GABA).

Pharmacodynamics

Vitamin B6 (pyridoxine) is a water-soluble vitamin used in the prophylaxis and treatment of vitamin B6 deficiency and peripheral neuropathy in those receiving isoniazid (isonicotinic acid hydrazide, INH). Vitamin B6 has been found to lower systolic and diastolic blood pressure in a small group of subjects with essential hypertension. Hypertension is another risk factor for atherosclerosis and coronary heart disease. Another study showed pyridoxine hydrochloride to inhibit ADP- or epinephrine-induced platelet aggregation and to lower total cholesterol levels and increase HDL-cholesterol levels, again in a small group of subjects. Vitamin B6, in the form of pyridoxal 5'-phosphate, was found to protect vascular endothelial cells in culture from injury by activated platelets. Endothelial injury and dysfunction are critical initiating events in the pathogenesis of atherosclerosis. Human studies have demonstrated that vitamin B6 deficiency affects cellular and humoral responses of the immune system. Vitamin B6 deficiency results in altered lymphocyte differentiation and maturation, reduced delayed-type hypersensitivity (DTH) responses, impaired antibody production, decreased lymphocyte proliferation and decreased interleukin (IL)-2 production, among other immunologic activities.