VITAFORCE SYRUP

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

• Iron deficiency anemia
• Prophylaxis of iron deficiency in at-risk populations
• Epithelial tissue changes such as atrophic glossitis and koilonychia

Dosage

Children: For children aged 1 month to 11 years: 0.25 mL per kilogram twice daily, with the total daily dose possibly given in 3 divided doses, not exceeding 20 mL per day. For children aged 12-17 years: 10 mL once daily.

Adults: The dose is calculated according to body weight and the iron deficit, specifying both the iron salt and formulation. For specific dosing, consult product literature.

Mechanism of action

Iron is necessary for the production of hemoglobin. Iron deficiency can lead to decreased production of hemoglobin and a microcytic, hypochromic anemia. Ferrous fumarate releases iron in the gastrointestinal tract, facilitating its absorption and subsequent incorporation into hemoglobin, thus alleviating anemia.

Pharmacodynamics

The major activity of supplemental iron, including ferrous fumarate, is in the prevention and treatment of iron deficiency anemia. Iron also has putative immune-enhancing, anticarcinogenic, and cognition-enhancing activities, supporting overall health and functionality.

Pharmacokinetics

Ferrous fumarate is absorbed in the gastrointestinal tract, with absorption being optimal in an acidic environment. The bioavailability can be influenced by dietary factors, such as the presence of certain foods or medications that may inhibit iron absorption. Once absorbed, iron is transported in the blood bound to transferrin and is stored in tissues as ferritin and hemosiderin. The elimination half-life of iron is variable and depends on the individual's iron status and the amount of iron stored.

Contra-indications

• Iron overload syndromes
• Repeated blood transfusions
• Porphyria cutanea tarda

Adverse effects

• Asthenia
• Drowsiness
• Urine discoloration
• Cold sweat
• Confusion
• Decreased level of consciousness
• Thrombophlebitis
• Headache
• Joint stiffness
• Pain in extremities
• Skin reactions
• Small intestinal bacterial overgrowth
• Thirst
• Nausea
• Constipation
• Diarrhea
• Decreased appetite

Interactions

• Iron absorption may be affected by antacids and certain medications that alter gastric pH.

Precautions

• Monitor iron status to avoid iron overload.
• Caution in patients with intestinal strictures or diverticular disease.
• Care in elderly patients and those on high doses.

Pregnancy

Iron is generally considered safe during pregnancy, but supplementation should be monitored to avoid overload.

Breast-feeding

Iron supplementation may be necessary for exclusively breast-fed infants if maternal iron stores are low.

Storage

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

Formulations

• Solution for injection (Iron as Iron sucrose 20 mg per 1 ml)
• Capsules containing iron formulations

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

• Iron-deficiency anemia (therapeutic)
• Iron-deficiency anemia (prophylactic)

Dosage

Children: For children aged 1 month to 11 years: 0.25 mL/kilogram twice daily. For children aged 12 to 17 years: 10 mL once daily.

Adults: 280 mg twice daily.

Mechanism of action

Ferrous sulfate acts as a source of iron, which is essential for the synthesis of hemoglobin, the protein in red blood cells that carries oxygen. Iron is absorbed in the intestines, where it is converted into a form that can be incorporated into hemoglobin. The mechanism involves transport proteins that facilitate iron uptake and incorporation into the heme group of hemoglobin.

Pharmacodynamics

The pharmacodynamic effect of ferrous sulfate is the increase in hemoglobin levels and improvement in symptoms of anemia, such as fatigue and weakness. Iron supplementation leads to increased erythropoiesis (red blood cell production) in the bone marrow, effectively correcting the deficit in iron stores and enhancing oxygen-carrying capacity.

Pharmacokinetics

Ferrous sulfate is absorbed in the gastrointestinal tract, particularly in the duodenum and proximal jejunum. The bioavailability of iron from ferrous sulfate can be affected by dietary factors, with enhanced absorption in acidic environments. Peak plasma concentrations typically occur within 2 to 6 hours post-administration. Iron is primarily stored in the liver and bone marrow, and any excess iron is excreted through feces, urine, and sweat.

Contra-indications

• Hypersensitivity to ferrous sulfate or any of its excipients
• Hemochromatosis
• Hemosiderosis
• Thalassemia
• Other anemias not due to iron deficiency

Adverse effects

• Gastrointestinal disturbances (nausea, constipation, diarrhea, abdominal pain)
• Dark stools
• Staining of teeth (with liquid formulations)
• Allergic reactions (rare)

Interactions

• Antacids may reduce the absorption of iron
• Tetracycline antibiotics may interfere with iron absorption
• Ascorbic acid (vitamin C) may enhance iron absorption
• Certain foods and beverages (e.g., tea, coffee, dairy) can decrease iron absorption

Precautions

• Use with caution in patients with peptic ulcer disease
• Monitor for signs of iron overload
• Assess the cause of anemia before initiation of therapy
• Keep out of reach of children to prevent accidental overdose

Pregnancy

Ferrous sulfate is generally considered safe for use during pregnancy to prevent or treat iron-deficiency anemia.

Breast-feeding

Ferrous sulfate is excreted in breast milk in small amounts but is considered safe for breastfeeding mothers.

Storage

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

Formulations

• Ferrous sulfate 200 mg tablets
• Ferrous sulfate 325 mg modified-release tablets
• Ferrous sulfate oral solution 140 mg/5 mL
• Ferrous sulfate drops

Indications

• Vitamin B2 deficiency
• Isoniazid-induced neuropathy (prophylaxis and treatment)
• Metabolic diseases
• Cystathioninuria
• Homocystinuria
• Wilson's disease
• Prevention of penicillamine-induced neuropathy

Mechanism of action

Riboflavin acts as a precursor to flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), which are essential coenzymes in various enzymatic reactions. It binds to riboflavin hydrogenase, riboflavin kinase, and riboflavin synthase, facilitating the production of FMN and FAD. These coenzymes are critical for normal tissue respiration and energy metabolism, influencing hydrogen transport in oxidative enzyme systems such as cytochrome C reductase and succinic dehydrogenase. Moreover, riboflavin contributes to the antioxidant activity by aiding in the production of reduced glutathione, a key antioxidant in the body.

Pharmacodynamics

Riboflavin is an easily absorbed, water-soluble micronutrient that supports energy production by assisting in the metabolism of fats, carbohydrates, and proteins. It is vital for red blood cell formation, antibody production, and regulating growth and reproduction. The vitamin plays a significant role in maintaining healthy skin, nails, and hair, as well as supporting thyroid activity. Riboflavin also has therapeutic implications in preventing or treating various eye disorders, including cataracts.

Pharmacokinetics

Riboflavin is rapidly absorbed in the gastrointestinal tract, with its bioavailability influenced by dietary intake. It is primarily excreted through urine, with excess intake leading to bright yellow urine, which is a harmless side effect. The vitamin does not accumulate in the body, necessitating regular dietary intake to maintain adequate levels.

Adverse effects

• Urine discolouration
• Peripheral neuritis

Precautions

• With intravenous use, risk of cardiovascular collapse; resuscitation facilities must be available and monitor closely.

Pregnancy

Crosses the placenta but no adverse effects reported; information at high doses limited.

Breast-feeding

Present in breast milk but no adverse effects reported; information at high doses limited.

Storage

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

Formulations

• 100 mg modified-release tablets
• 50 mg capsules
• 100 mg capsules
• 100 mg tablets
• Oral solution

Indications

• Vitamin B1 deficiency
• Wernicke-Korsakoff syndrome
• Beriberi
• Isoniazid-induced neuropathy (prophylaxis and treatment)
• Severe depletion or malabsorption of vitamins B and C

Dosage

Adults: For vitamin deficiency: 25–100 mg daily. For severe deficiency: 200–300 mg daily in divided doses. For

Mechanism of action

Thiamine functions primarily as a precursor for several phosphorylated active forms, which act as coenzymes in metabolic pathways. It reduces intracellular protein glycation by redirecting glycolytic flux and supports the synthesis of nucleic acids necessary for cell survival and proliferation. Additionally, thiamine has been shown to inhibit glucose-induced proliferation of endothelial cells, thus possibly playing a role in the modulation of vascular health.

Pharmacodynamics

Thiamine exhibits antioxidant properties and contributes to erythropoiesis, cognitive function, and mood regulation. It has protective effects against oxidative stress, particularly in neuronal tissues, where deficiency can lead to neuronal death due to increased free radical production. Thiamine also modulates glucose metabolism, influencing smooth muscle cell proliferation and potentially impacting the progression of atherosclerosis.

Pharmacokinetics

Thiamine is rapidly absorbed from the gastrointestinal tract, primarily in the jejunum, and is distributed throughout the body, with higher concentrations found in the liver, heart, and brain. It is excreted in urine, and its half-life is relatively short. The vitamin is converted into active forms within tissues, including thiamine diphosphate (TDP), which is the coenzyme form involved in carbohydrate metabolism. The body does not store significant amounts of thiamine, making regular dietary intake essential.

Adverse effects

• Allergic reactions
• Anaphylaxis (rare)
• Gastrointestinal disturbances

Precautions

• Facilities for treating anaphylaxis should be available when parenteral thiamine is administered
• Use with caution in patients with a history of hypersensitivity to thiamine

Pregnancy

Thiamine crosses the placenta but no adverse effects have been reported. Information regarding high doses is limited.

Breast-feeding

Severely thiamine-deficient mothers should avoid breast-feeding as thiamine is present in breast milk.

Storage

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

Formulations

• Thiamine hydrochloride 20 mg/ml oral solution
• Thiamine hydrochloride 50 mg tablets
• Thiamine hydrochloride 100 mg modified-release tablets
• Thiamine hydrochloride oral suspension

Indications

• Topical treatment of skin wounds
• Moisturizing dry skin
• Management of minor burns
• Soothing irritations and inflammation of the skin

Dosage

Children: Refer to the BNF for Children for specific dosing

Adults: Apply to the affected area as needed, following the specific product instructions.

Mechanism of action

Dexpanthenol is enzymatically converted to pantothenic acid, which is integral to the formation of coenzyme A. This coenzyme acts as a cofactor in numerous enzymatic reactions, particularly those related to protein metabolism in epithelial tissues. The topical application of dexpanthenol promotes fibroblast proliferation and accelerates wound healing through enhanced re-epithelialization. It also increases the availability of coenzyme A for acetylcholine synthesis, which can enhance intestinal motility by improving peristalsis.

Pharmacodynamics

Dexpanthenol, through its conversion to pantothenic acid, plays a vital role in the synthesis of coenzyme A, which is necessary for various metabolic processes, including the transfer of acetyl groups. It directly influences the production of acetylcholine, the neurotransmitter responsible for parasympathetic nervous system functions, which include maintaining normal intestinal activity. A deficiency in acetylcholine can lead to reduced peristalsis and conditions such as adynamic ileus.

Pharmacokinetics

Dexpanthenol is well absorbed when applied topically. It penetrates the skin effectively, reaching the underlying tissues where it can exert its biological effects. The metabolism of dexpanthenol involves its conversion to pantothenic acid, which further participates in the synthesis of coenzyme A. The elimination half-life and extent of systemic absorption vary based on the formulation and route of administration, but topical use typically results in low systemic exposure.

Adverse effects

• Skin irritation
• Allergic reactions

Precautions

• Use with caution in patients with known allergies to dexpanthenol or related compounds.

Pregnancy

Dexpanthenol is generally considered safe for use during pregnancy, but it is advisable to consult a healthcare provider before use.

Breast-feeding

Dexpanthenol is considered safe during breastfeeding, but consult a healthcare provider for specific recommendations.

Storage

Store at room temperature, away from light and moisture. Keep out of reach of children.

Formulations

• Topical cream
• Topical ointment
• Topical solution

Indications

• Malabsorption syndromes
• Crohn's disease
• Cystic fibrosis
• Short bowel syndrome
• Severe food allergies
• Inability to meet nutritional needs through standard diets

Dosage

Children: Refer to specific formulations for dosing, as paediatric dosages depend on the product and the child's nutritional needs.

Adults: Refer to specific formulations for dosing, as adult dosages vary based on the product used and the patient's nutritional requirements.

Mechanism of action

Elemental formulations provide nutrients in their simplest forms, which are readily absorbed in the small intestine. This bypasses complex digestive processes, making them suitable for individuals with compromised digestion or absorption capabilities. The nutrients in these formulations include amino acids, simple carbohydrates, and fatty acids, which can be directly utilized by the body's metabolic pathways.

Pharmacodynamics

Elemental formulations help restore nutritional balance by supplying essential macronutrients and micronutrients needed for metabolic processes. They support growth, maintain energy levels, and promote healing in patients with malabsorption or increased nutritional needs. The bioavailability of nutrients in elemental forms is typically high, allowing for efficient uptake and utilization by the body.

Pharmacokinetics

Following administration, elemental nutrients are absorbed in the gastrointestinal tract, primarily in the jejunum and ileum. The rate of absorption can vary based on the specific formulation and the individual's gastrointestinal health. Once absorbed, these nutrients enter systemic circulation and are transported to various tissues for utilization in metabolic processes. The elimination of unabsorbed nutrients occurs primarily through feces.

Adverse effects

• Nausea
• Vomiting
• Diarrhea
• Constipation
• Stomach cramps
• Dark stools
• Metallic taste
• Allergic reactions

Precautions

• Use with caution in patients with a history of gastrointestinal disorders.
• Monitor for signs of iron overload in patients receiving multiple iron products.
• Assess for the need for supplementation in patients with conditions causing malabsorption.

Pregnancy

Iron is essential during pregnancy, but supplementation should be guided by clinical need and under healthcare supervision.

Breast-feeding

Iron is excreted in breast milk; supplementation may be necessary depending on maternal iron status.

Storage

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

Formulations

• Oral tablets
• Liquid formulations
• Injectable solutions

Indications

• Iron deficiency anemia
• Iron deficiency due to inadequate dietary intake
• Anemia associated with chronic disease
• Pregnancy-related anemia

Dosage

Children: Refer to the BNF for Children for specific dosing recommendations based on age and weight.

Adults: Refer to the BNF for specific dosing recommendations, generally, adults may require 100-200 mg of elemental iron daily divided into several doses.

Mechanism of action

Ferrous ions (Fe2+) play a vital role in hemoglobin production by participating in the synthesis of heme, the iron-containing compound essential for oxygen transport in the blood. In addition, iron is a cofactor for various enzymes involved in metabolic pathways, including those related to DNA synthesis and energy production.

Pharmacodynamics

The pharmacodynamic effects of ferrous include increased hemoglobin synthesis, improved oxygen transport, and enhanced cellular energy metabolism. Supplementation leads to an increase in serum ferritin levels and replenishment of iron stores in the body, which is particularly beneficial in cases of iron deficiency anemia.

Pharmacokinetics

Ferrous iron is absorbed primarily in the duodenum and upper jejunum of the small intestine. The absorption rate can be influenced by various factors, including the presence of food, the form of iron, and individual patient characteristics. Once absorbed, ferrous is transported in the bloodstream bound to transferrin, and it is stored in the liver, spleen, and bone marrow as ferritin. The elimination half-life of iron is not well-defined as it is not excreted directly but rather recycled in the body.

Pregnancy

Not contraindicated, but iron supplementation should be done under medical supervision.

Breast-feeding

Iron is excreted in breast milk, but supplementation is generally considered safe.

Storage

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

Indications

• Hypophosphatemia
• Osteomalacia
• Rickets
• Certain renal disorders
• Malnutrition

Dosage

Children: Refer to clinical guidelines or specific product information for dosing recommendations.

Adults: Refer to clinical guidelines or specific product information for dosing recommendations.

Mechanism of action

Hypophosphate acts by providing inorganic phosphate ions that are crucial for various biochemical pathways. It helps in the synthesis of ATP (adenosine triphosphate), nucleic acids, and phospholipids. The availability of phosphate is critical for cellular energy transfer and metabolic processes.

Pharmacodynamics

Hypophosphate contributes to the regulation of phosphate levels in the body, affecting cellular functions, bone mineralization, and energy metabolism. It can enhance the activity of certain enzymes involved in metabolic pathways and plays a role in maintaining acid-base balance.

Pharmacokinetics

Hypophosphate is absorbed in the gastrointestinal tract and its absorption may be influenced by dietary factors and the presence of other minerals. Once in the bloodstream, phosphate is widely distributed and utilized by various tissues. The kidneys regulate phosphate excretion, maintaining homeostasis based on the body's needs.

Adverse effects

• Gastrointestinal disturbances
• Hypocalcemia
• Hyperphosphatemia
• Nausea
• Diarrhea

Interactions

• Aluminium-containing antacids may reduce phosphate absorption
• Calcium supplements may interact with phosphate levels
• Iron supplements may affect phosphate absorption

Precautions

• Use with caution in patients with renal impairment
• Monitor serum phosphate and calcium levels
• Consider dietary phosphorus intake

Pregnancy

Safety in pregnancy has not been established. Use only if clearly needed.

Breast-feeding

Phosphate is excreted in breast milk; use with caution.

Storage

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

Formulations

• Oral tablets
• Oral solutions
• Injectable forms

Indications

• Metabolic acidosis
• Lactic acidosis
• Energy substrate in critical illness
• Monitoring tissue perfusion and oxygenation

Dosage

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

Adults: Refer to specific guidelines based on clinical context as dosing is highly variable and situation-dependent.

Mechanism of action

Lactate acts as a signaling molecule and energy substrate in various physiological and pathological processes. It is involved in the modulation of several metabolic pathways, including the Cori cycle and Krebs cycle. Lactate also participates in metabolic reprogramming, especially in cancer cells, where it can promote tumor growth and survival by providing an alternative energy source and influencing cellular signaling pathways such as the PI3K/AKT/mTOR pathway.

Pharmacodynamics

Lactate plays a vital role in energy metabolism. It can be oxidized back to pyruvate by lactate dehydrogenase, entering the Krebs cycle for ATP production. In addition to serving as an energy substrate, lactate impacts pH regulation and can influence the function of various immune cells. Its levels can indicate the state of oxygen delivery and utilization in tissues, thus serving as a marker for metabolic stress.

Pharmacokinetics

Lactate is produced primarily in the cytoplasm during glycolysis, with its concentration in the blood reflecting the balance between production and clearance. It is metabolized predominantly in the liver, where it can be converted back to glucose or utilized in the Krebs cycle. Lactate levels can vary based on factors such as exercise, tissue hypoxia, and metabolic conditions.

Pregnancy

Lactate is generally regarded as safe during pregnancy as it is a naturally occurring metabolite in the body, but specific clinical advice should be sought.

Breast-feeding

Lactate is considered safe during breastfeeding as it is a normal component of human metabolism, but consult a healthcare provider for personalized advice.

Storage

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

Indications

• Dermatitis
• Acne
• Rosacea
• Hyperpigmentation
• Skin aging

Dosage

Children: Refer to the BNF for Children for specific dosing guidelines for paediatric patients.

Adults: Refer to the BNF for specific dosing guidelines based on the condition being treated.

Mechanism of action

Niacinamide functions primarily as a precursor to NAD and NADP, which are crucial for numerous enzymatic reactions in the body. It is involved in the NAD salvage pathway, which recycles nicotinamide for NAD synthesis. This process is vital for cellular energy production and metabolic processes. Niacinamide also has anti-inflammatory properties, which may contribute to its effects in skin health.

Pharmacodynamics

Niacinamide exhibits various pharmacological effects, including enhancing skin barrier function, reducing inflammation, and improving skin pigmentation. It has been shown to modulate keratinocyte function, improve collagen synthesis, and decrease the synthesis of sebum, thereby providing beneficial effects in conditions like acne and rosacea.

Pharmacokinetics

Niacinamide is readily absorbed from the gastrointestinal tract. It is distributed widely throughout the body and can cross biological membranes. The metabolism of niacinamide primarily occurs in the liver through methylation and conjugation, and it is excreted in urine as metabolites. The half-life of niacinamide is approximately 1-2 hours, and its effects can be prolonged due to its role in NAD synthesis.

Pregnancy

No evidence of harm, but use only if clearly needed.

Breast-feeding

Considered safe to use while breastfeeding.

Storage

Store in a cool, dry place away from light.

Formulations

• {'type': 'Topical cream', 'concentration': 'Various concentrations available'}
• {'type': 'Oral tablets', 'concentration': '100 mg, 250 mg, 500 mg'}

Mechanism of action

Excessive palmitoylcarnitine formation and exhausted L-carnitine stores lead to energy depletion, which, along with attenuated acetylcholine synthesis and oxidative stress, are main mechanisms behind palmitate-induced neuronal loss. High levels of palmitate exposure are suggested to contribute to diabetic neuropathy and gastrointestinal dysregulation. Additionally, palmitate negatively regulates acetyl-CoA carboxylase, thereby preventing further palmitate generation.

Pharmacodynamics

Palmitate is the first fatty acid generated during lipogenesis and serves as a precursor for the synthesis of longer fatty acids. The presence of palmitate inhibits acetyl-CoA carboxylase, reducing the conversion of acetyl-ACP to malonyl-ACP, which subsequently decreases the synthesis of new palmitate. This feedback mechanism is crucial for maintaining lipid homeostasis within the body.

Pharmacokinetics

Palmitate is absorbed from dietary sources and can also be synthesized endogenously in the liver and adipose tissue. Once in circulation, it is transported via chylomicrons or albumin. The metabolism of palmitate occurs primarily in the mitochondria through fatty acid oxidation, generating acetyl-CoA, which can enter the citric acid cycle for energy production. The overall kinetics of palmitate are influenced by dietary intake, metabolic demand, and hormonal regulation.

Pregnancy

Palmitate is classified as a category C drug. Animal reproduction studies have not been conducted, and there are no adequate and well-controlled studies in pregnant women. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

There are no data on the excretion of palmitate in human milk. Caution should be exercised when administering to nursing mothers.

Storage

Store at room temperature, away from light and moisture. Keep the container tightly closed.

Formulations

• Palmitate 500 mg softgel
• Palmitate 1000 mg softgel

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

Indications

• Thiamine deficiency
• Wernicke's encephalopathy
• Beriberi
• Alcoholism-related complications
• Certain metabolic disorders

Dosage

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

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

Mechanism of action

Thiamine is a coenzyme for several important enzymatic reactions, including the pyruvate dehydrogenase complex and alpha-ketoglutarate dehydrogenase. It is essential for converting carbohydrates into energy, facilitating the metabolism of glucose, and maintaining normal nerve function.

Pharmacodynamics

Thiamine deficiency leads to impaired carbohydrate metabolism, which can result in neurological and cardiovascular dysfunction. Supplementation with thiamine helps restore normal metabolic function and can alleviate symptoms associated with deficiency, such as Wernicke's encephalopathy and Beriberi. It also plays a role in the synthesis of neurotransmitters and in maintaining myelin integrity.

Pharmacokinetics

Thiamine is readily absorbed from the gastrointestinal tract, with peak plasma concentrations occurring within 1-2 hours after oral administration. It is distributed throughout the body, primarily in the liver, kidneys, and heart. Thiamine is metabolized in the liver to its active form, thiamine pyrophosphate. It has a biological half-life of about 9-18 days and is excreted primarily in the urine. Excess thiamine is excreted, making toxicity rare.

Adverse effects

• Allergic reactions
• Hypersensitivity reactions
• Gastrointestinal disturbances

Interactions

• May interact with certain diuretics, leading to altered thiamine levels

Precautions

• Use with caution in patients with renal impairment
• Monitor patients with a history of thiamine deficiency

Pregnancy

Thiamine is considered safe during pregnancy, as it is an essential nutrient.

Breast-feeding

Thiamine is excreted in breast milk, but supplementation is generally considered safe for breastfeeding mothers.

Storage

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

Formulations

• Thiamine hydrochloride injection
• Thiamine hydrochloride oral tablets
• Thiamine hydrochloride oral solution

Indications

• Vitamin deficiency syndromes (e.g., scurvy for vitamin C deficiency, rickets for vitamin D deficiency)
• Support for immune function
• Antioxidant support
• Bone health maintenance
• Vision health
• Energy metabolism support

Dosage

Children: Refer to the BNF for Children for specific vitamin dosing guidelines, which depend on age and nutritional requirements.

Adults: Refer to specific vitamin guidelines as dosage varies significantly depending on the type of vitamin and individual needs.

Mechanism of action

Vitamins function primarily as coenzymes or precursors for coenzymes in enzymatic reactions. For instance, B vitamins are involved in energy metabolism, while vitamins A, C, D, E, and K support various physiological functions including vision, antioxidant activity, calcium regulation, and blood clotting. Each vitamin has a unique mechanism of action based on its structure and role in the body.

Pharmacodynamics

Vitamins exert their effects at the cellular level, influencing metabolic pathways, gene expression, and immune responses. For example, vitamin D regulates calcium and phosphate homeostasis, while vitamin A is crucial for vision and immune function. Deficiencies in vitamins can lead to a range of disorders, highlighting their importance in maintaining health.

Pharmacokinetics

The pharmacokinetics of vitamins vary widely. Fat-soluble vitamins (A, D, E, and K) are stored in liver and adipose tissues and can be released into circulation as needed. Water-soluble vitamins (B-complex and C) are not stored and must be consumed regularly, with excess amounts excreted in urine. Absorption rates, half-lives, and distribution can also differ based on the specific vitamin and individual metabolic factors.

Interactions

• tretinoin+vitamin: Severe (increases risk of vitamin toxicity)
• retinoids+vitamin: Severe (increases risk of vitamin toxicity)
• retinoids+vitamin: Moderate (increases risk of toxicity)
• carbamazepine+vitamin: Unknown (decreases effects)
• cobicistat+vitamin: Unknown (increases exposure)
• vitamin D substances+digoxin: Unknown (increases risk of toxicity)
• idelalisib+vitamin: Unknown (increases exposure)
• clarithromycin+vitamin: Unknown (increases exposure)

Pregnancy

Consult healthcare professional before use. Vitamin supplementation during pregnancy should be carefully managed to avoid hypervitaminosis.

Breast-feeding

Consult healthcare professional before use. Some vitamins can pass into breast milk and may affect the infant.

Storage

Store in a cool, dry place, away from direct sunlight. Ensure it is kept out of reach of children.

Formulations

• {'name': 'Vitamin A', 'form': 'Capsule', 'strength': '10000 IU'}
• {'name': 'Vitamin D', 'form': 'Tablet', 'strength': '1000 IU'}
• {'name': 'Vitamin E', 'form': 'Softgel', 'strength': '400 IU'}

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

Iron is necessary for the production of hemoglobin. Iron-deficiency can lead to decreased production of hemoglobin and a microcytic, hypochromic anemia.

Pharmacodynamics

The major activity of supplemental iron is in the prevention and treatment of iron deficiency anemia. Iron has putative immune-enhancing, anticarcinogenic and cognition-enhancing activities.

Mechanism of action

Iron is necessary for the production of hemoglobin. Iron-deficiency can lead to decreased production of hemoglobin and a microcytic, hypochromic anemia.

Pharmacodynamics

The major activity of supplemental iron is in the prevention and treatment of iron deficiency anemia. Iron has putative immune-enhancing, anticarcinogenic and cognition-enhancing activities.

Mechanism of action

Binds to riboflavin hydrogenase, riboflavin kinase, and riboflavin synthase. Riboflavin is the precursor of flavin mononucleotide (FMN, riboflavin monophosphate) and flavin adenine dinucleotide (FAD). The antioxidant activity of riboflavin is principally derived from its role as a precursor of FAD and the role of this cofactor in the production of the antioxidant reduced glutathione. Reduced glutathione is the cofactor of the selenium-containing glutathione peroxidases among other things. The glutathione peroxidases are major antioxidant enzymes. Reduced glutathione is generated by the FAD-containing enzyme glutathione reductase. Riboflavin is converted to 2 coenzymes, flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD), which are necessary for normal tissue respiration. Riboflavin is also required for activation of pyridoxine, conversion of tryptophan to niacin, and may be involved in maintaining erythrocyte integrity. Riboflavin functions as the coenzyme for flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN), which primarily influence hydrogen transport in oxidative enzyme systems (eg, cytochrome C reductase, succinic dehydrogenase, xanthine oxidase). Two active forms of riboflavin exist ... coenzyme flavin mononucleotide (FMN) and coenzyme flavin adenine dinucleotide (FAD). They are formed by reaction of riboflavin with 1 and 2 molecules of ATP as follow: riboflavin + ATP = riboflavin-P (FMN) + ADP; FMN + ATP = riboflavin-ADP (FAD) + PP. Riboflavin is a water-soluble, yellow, fluorescent compound. The primary form of the vitamin is as an integral component of the coenzymes flavin mononucleotide (FMN) and flavin-adenine dinucleotide (FAD). It is in these bound coenzyme forms that riboflavin functions as a catalyst for redox reactions in numerous metabolic pathways and in energy production. ... The redox reactions in which flavocoenzymes participate include flavoprotein-catalyzed dehydrogenations that are both pyridine nucleotide (niacin) dependent and independent, reactions with sulfur-containing compounds, hydroxylations, oxidative decarboxylations (involving thiamin as its pyrophosphate), dioxygenations, and reduction of oxygen to hydrogen peroxide. There are obligatory roles of flavocoenzymes in the formation of some vitamins and their coenzymes. For example, the biosynthesis of two niacin-containing coenzymes from tryptophan occurs via FAD-dependent kynurenine hydroxylase, an FMN-dependent oxidase catalyzes the conversion of the 5'-phosphates of vitamin B6 to coenzymic pyridoxal 5'-phosphate, and an FAD-dependent dehydrogenase reduces 5,10-methylene-tetrahydrofolate to the 5'-methyl product that interfaces with the B12-dependent formation of methionine from homocysteine and thus with sulfur amino acid metabolism. For more Mechanism of Action (Complete) data for Riboflavin (7 total), please visit the HSDB record page.

Pharmacodynamics

Riboflavin or vitamin B2 is an easily absorbed, water-soluble micronutrient with a key role in maintaining human health. Like the other B vitamins, it supports energy production by aiding in the metabolising of fats, carbohydrates, and proteins. Vitamin B2 is also required for red blood cell formation and respiration, antibody production, and for regulating human growth and reproduction. It is essential for healthy skin, nails, hair growth and general good health, including regulating thyroid activity. Riboflavin also helps in the prevention or treatment of many types of eye disorders, including some cases of cataracts.

Mechanism of action

It is thought that the mechanism of action of thiamine on endothelial cells is related to a reduction in intracellular protein glycation by redirecting the glycolytic flux. Thiamine is mainly the transport form of the vitamin, while the active forms are phosphorylated thiamine derivatives. Natural derivatives of thiamine phosphate, such as thiamine monophosphate (ThMP), thiamine diphosphate (ThDP), also sometimes called thiamine pyrophosphate (TPP), thiamine triphosphate (ThTP), and thiamine triphosphate (AThTP), that act as coenzymes in addition to their each unique biological functions. Metabolic control analysis predicts that stimulators of transketolase enzyme synthesis such as thiamin (vitamin B-1) support a high rate of nucleic acid ribose synthesis necessary for tumor cell survival, chemotherapy resistance, and proliferation. Metabolic control analysis also predicts that transketolase inhibitor drugs will have the opposite effect on tumor cells. This may have important implications in the nutrition and future treatment of patients with cancer.

Pharmacodynamics

Thiamine is a vitamin with antioxidant, erythropoietic, cognition-and mood-modulatory, antiatherosclerotic, putative ergogenic, and detoxification activities. Thiamine has been found to protect against lead-induced lipid peroxidation in rat liver and kidney. Thiamine deficiency results in selective neuronal death in animal models. The neuronal death is associated with increased free radical production, suggesting that oxidative stress may play an important early role in brain damage associated with thiamine deficiency. Thiamine plays a key role in intracellular glucose metabolism and it is thought that thiamine inhibits the effect of glucose and insulin on arterial smooth muscle cell proliferation. Inhibition of endothelial cell proliferation may also promote atherosclerosis. Endothelial cells in culture have been found to have a decreased proliferative rate and delayed migration in response to hyperglycemic conditions. Thiamine has been shown to inhibit this effect of glucose on endothelial cells.

Mechanism of action

Dexpanthenol is an alcohol derivative of pantothenic acid, a component of the B complex vitamins and an essential component of a normally functioning epithelium. Dexpanthenol is enzymatically cleaved to form pantothenic acid, which is an essential component of Coenzyme A, which acts as a cofactor in many enzymatic reactions that are important for protein metabolism in the epithelium. Dermatological effects of the topical use of dexpanthenol include increased fibroblast proliferation and accelerated re-epithelialization in wound healing. Furthermore, it acts as a topical protectant, moisturizer, and has demonstrated anti-inflammatory properties. This alcohol ... is said to increase the amount of coenzyme A available for the synthesis of acetylcholine. Increased formation of acetylcholine is thought to increase peristalsis and intestinal tone. ... To test the functional effect of pantothenate on dermal fibroblasts, cells were cultured and in vitro proliferation tests were performed using a standardized scratch test procedure. For all three donors analyzed, a strong stimulatory effect of pantothenate at a concentration of 20 ug/mL on the proliferation of cultivated dermal fibroblasts was observed. To study the molecular mechanisms resulting in the proliferative effect of pantothenate, gene expression was analyzed in dermal fibroblasts cultivated with 20 ug/mL of pantothenate compared with untreated cells using the GeneChip Human Exon 1.0 ST Array. A number of significantly regulated genes were identified including genes coding for interleukin (IL)-6, IL-8, Id1, HMOX-1, HspB7, CYP1B1 and MARCH-II. Regulation of these genes was subsequently verified by quantitative real-time polymerase chain reaction analysis. Induction of HMOX-1 expression by pantothenol and pantothenic acid in dermal cells was confirmed on the protein level using immunoblots. Functional studies revealed the enhanced suppression of free radical formation in skin fibroblasts cultured with panthenol. In conclusion, these studies provided new insight in the molecular mechanisms linked to the stimulatory effect of pantothenate and panthenol on the proliferation of dermal fibroblasts. /Calcium pantotenate/ ... Pantothenic acid, pantothenol and other derivatives ... are precursors of CoA /that/ protect cells and whole organs against peroxidative damage by increasing the content of cell glutathione...

Pharmacodynamics

Pantothenic acid is a precursor of coenzyme A, which serves as a cofactor for a variety of enzyme-catalyzed reactions involving transfer of acetyl groups. The final step in the synthesis of acetylcholine consists of the choline acetylase transfer of acetyl group from acetylcoenzyme A to choline. Acetylcholine is the neurohumoral transmitter in the parasympathetic system and as such maintains the normal functions of the intestine. Decrease in acetylcholine content would result in decreased peristalsis and in extreme cases adynamic ileus.

Mechanism of action

... Excessive palmitoylcarnitine formation and exhausted L-carnitine stores leading to energy depletion, attenuated acetylcholine synthesis and oxidative stress to be main mechanisms behind PA-induced neuronal loss.High PA exposure is suggested to be a factor in causing diabetic neuropathy and gastrointestinal dysregulation. ... First phase insulin release response was lost in these islets. FFAs slightly increased the insulin output of normal fresh pancreas beta-cells. However, chronic exposure to FFAs resulted in loss of first phase insulin release and blunted insulin secretion response to various levels of D-glucose stimulation.

Pharmacodynamics

Palmitic acid is the first fatty acid produced during lipogenesis (fatty acid synthesis) and from which longer fatty acids can be produced. Palmitate negatively feeds back on acetyl-CoA carboxylase (ACC) which is responsible for converting acetyl-ACP to malonyl-ACP on the growing acyl chain, thus preventing further palmitate generation

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.