Rotas 20

Mechanism of action

Rosuvastatin acts as a competitive inhibitor of HMG-CoA reductase, the enzyme responsible for converting HMG-CoA to mevalonate, a crucial step in cholesterol biosynthesis. By inhibiting this enzyme, rosuvastatin decreases hepatic cholesterol levels, which in turn upregulates the expression of hepatic LDL receptors, enhancing the uptake of LDL cholesterol from the circulation. Additionally, it reduces the hepatic synthesis of very low-density lipoprotein (VLDL). Beyond its lipid-lowering effects, rosuvastatin exhibits pleiotropic effects, improving endothelial function, stabilizing atherosclerotic plaques, reducing oxidative stress and inflammation, and inhibiting thrombogenic responses.

Pharmacodynamics

Rosuvastatin effectively lowers total cholesterol, LDL-C, apolipoprotein B (apoB), and triglycerides while raising HDL-C levels. High levels of LDL-C and triglycerides, along with low HDL-C, are associated with an increased risk of atherosclerosis and cardiovascular disease (CVD). By improving the total cholesterol to HDL-C ratio, rosuvastatin reduces the risk of cardiovascular morbidity and mortality. Statins, including rosuvastatin, are considered cost-effective in managing CVD due to their significant impact on reducing LDL levels and overall cardiovascular risk.

Pharmacokinetics

Rosuvastatin is rapidly absorbed after oral administration, with peak plasma concentrations typically occurring within 3 to 5 hours. It has a bioavailability of approximately 20%, and its absorption is not significantly affected by food. The drug is primarily metabolized in the liver, and about 90% of the administered dose is excreted in the faeces, with the remainder eliminated via urine. The half-life of rosuvastatin is approximately 19 hours, allowing for once-daily dosing. Renal impairment may

Contra-indications

• Active liver disease
• Pregnancy
• Known hypersensitivity to rosuvastatin or any excipients

Adverse effects

• Muscle weakness
• Myopathy
• Rhabdomyolysis
• Abnormal liver function tests
• Gastrointestinal disturbances
• Headache
• Dizziness
• Allergic reactions including angioedema

Interactions

• Ciclosporin increases exposure
• Darolutamide increases exposure
• Letermovir increases exposure
• Tedizolid increases exposure
• Voxilaprevir with sofosbuvir and velpatasvir markedly increases exposure
• Dronedarone moderately increases exposure
• Leflunomide moderately increases exposure
• Roxadustat moderately increases exposure
• Apalutamide decreases exposure
• Eslicarbazepine decreases exposure

Precautions

• Monitor liver function tests prior to and during treatment
• Use with caution in patients with a history of muscle disorders
• Caution in patients with renal impairment
• Consider alternative therapy for patients with a history of statin intolerance

Pregnancy

Manufacturer advises against use during pregnancy due to potential harm to the fetus.

Breast-feeding

Manufacturer advises avoiding use during breastfeeding, as small amounts may be present in breast milk.

Storage

Store in a cool, dry place below 30°C. Protect from light.

Formulations

• Tablets: 5 mg, 10 mg, 20 mg, 40 mg
• Oral suspension
• Oral solution

Mechanism of action

Carbonate ions participate in buffering reactions that help maintain pH homeostasis in biological systems. They can react with acids to form bicarbonate and carbon dioxide, thus neutralizing excess acidity in the body. This mechanism is crucial in processes such as respiration and metabolism.

Pharmacodynamics

As a buffer, carbonate helps to stabilize pH levels in different biological environments, preventing excessive acidity or alkalinity that could impair cellular functions. It is involved in the transport of carbon dioxide in the blood and plays a role in maintaining the acid-base equilibrium necessary for physiological processes.

Pharmacokinetics

Carbonate ions are readily absorbed in the gastrointestinal tract when ingested and can be found in various body fluids. They are involved in the bicarbonate buffering system, where they are converted to bicarbonate (HCO3-) and carbon dioxide (CO2) through reactions with acids. The kidneys regulate the levels of bicarbonate and carbonate in the body, excreting or reabsorbing them as needed to maintain homeostasis.

Pregnancy

There is no specific information available regarding the use of carbonate compounds during pregnancy. Consult a healthcare provider for advice.

Breast-feeding

There is no specific information available regarding the use of carbonate compounds while breastfeeding. Consult a healthcare provider for advice.

Storage

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

Indications

• Constipation
• Dietary fiber supplementation
• Irritable bowel syndrome
• Diverticular disease
• Weight management

Dosage

Children: Refer to appropriate guidelines for specific dosage; generally taken with adequate fluid intake.

Adults: Refer to appropriate guidelines for specific dosage; generally taken with adequate fluid intake.

Mechanism of action

Cellulose acts primarily as a bulk-forming laxative. It absorbs water in the intestines, which increases stool bulk and stimulates peristalsis, thus facilitating bowel movements. Additionally, cellulose is not digestible by human enzymes, leading to fermentation by gut bacteria, which may enhance gut health and alter gut microbiota composition.

Pharmacodynamics

Cellulose increases stool weight and frequency of bowel movements. It works by retaining water in the intestines, leading to softer stools and improved passage through the gastrointestinal tract. The bulking effect of cellulose can help alleviate constipation and promote overall digestive health. It may also play a role in cholesterol reduction and glycemic control through its effects on digestion and absorption of nutrients.

Pharmacokinetics

Cellulose is not absorbed into the bloodstream due to its indigestible nature. Instead, it passes through the gastrointestinal tract, where it adds bulk to the stool. Its fermentation by colonic bacteria produces short-chain fatty acids, which may have beneficial effects on colon health. The onset of action for cellulose as a laxative can vary but is generally within 24 to 72 hours after ingestion.

Adverse effects

• Bloating
• Flatulence
• Diarrhea
• Abdominal discomfort

Precautions

• Use with caution in patients with a history of gastrointestinal disorders.
• Monitor for potential allergic reactions in sensitive individuals.

Pregnancy

Cellulose is generally considered safe during pregnancy as it is a non-toxic, indigestible fiber.

Breast-feeding

Cellulose is also considered safe during breastfeeding; it is excreted in breast milk in negligible amounts.

Storage

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

Formulations

• Powder
• Capsules
• Tablets
• Granules

Indications

• Used as an excipient in solid dosage forms
• Facilitates drug disintegration and dissolution

Dosage

Children: Refer to specific product formulation guidelines as crospovidone is used as an excipient and does not have a direct dosage.

Adults: Refer to specific product formulation guidelines as crospovidone is used as an excipient and does not have a direct dosage.

Mechanism of action

Crospovidone acts by rapidly absorbing water and swelling upon contact with moisture. This action leads to the disintegration of solid dosage forms, thus increasing the surface area of the active ingredients and promoting their dissolution and subsequent absorption in the gastrointestinal tract. It does not affect the pH of the formulation, ensuring that the active ingredients remain stable.

Pharmacodynamics

Crospovidone exhibits properties that enhance the bioavailability of active ingredients in pharmaceutical formulations. Its ability to rapidly disintegrate tablets and capsules leads to quicker release and absorption of the drug into systemic circulation. As a disintegrant, it aids in the effective delivery of drugs that may otherwise be poorly soluble.

Pharmacokinetics

Crospovidone itself is not absorbed systemically when administered orally. It remains in the gastrointestinal tract, where it performs its function as a disintegrant. The pharmacokinetic profile of drugs formulated with crospovidone may be influenced by the enhanced dissolution and absorption rates provided by this excipient.

Pregnancy

Crospovidone is considered to have low toxicity and is generally regarded as safe for use during pregnancy, but specific studies are limited.

Breast-feeding

There is insufficient data on the excretion of crospovidone in human milk, but it is deemed safe for use during breastfeeding.

Storage

Store in a cool, dry place away from light and moisture, in tightly closed containers.

Formulations

• Powder
• Tablets

Indications

• Anxiety disorders
• Nausea and vomiting
• Allergic conditions
• Preoperative sedation
• Pruritus

Dosage

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

Adults: Refer to the BNF for specific dosing guidelines based on the indication and patient characteristics.

Mechanism of action

Hydroxyzine works by antagonizing the H1 histamine receptors, leading to a reduction in the effects of histamine in the body. This action helps alleviate symptoms of allergic reactions and promotes sedation. Additionally, it may exert effects on serotonin and adrenergic receptors, which could contribute to its anxiolytic properties. Hydroxyzine is also involved in various metabolic pathways, including selenium metabolism and the degradation of reactive oxygen species.

Pharmacodynamics

The pharmacodynamic effects of hydroxyzine include sedation, anxiolysis, and reduction of allergic symptoms. Its sedative effects can make it useful in managing anxiety and inducing sleep, while its antihistaminic properties help to relieve symptoms such as itching and rashes associated with allergic reactions. The onset of action is typically within 15 to 30 minutes when taken orally, with peak effects occurring within 1 to 2 hours.

Pharmacokinetics

Hydroxyzine is well absorbed from the gastrointestinal tract, with peak plasma concentrations occurring approximately 2 hours after oral administration. It is extensively metabolized in the liver, with metabolites, including cetirizine, possessing their own therapeutic effects. Hydroxyzine has a half-life of approximately 20 hours, allowing for once or twice daily dosing. It is primarily excreted in the urine, with less than 1% of the unchanged drug found in urine.

Interactions

• hydroxyzine+antiepileptics: Severe (increases risk of overheating and dehydration)
• hydroxyzine+zonisamide: Severe (increases risk of overheating and dehydration)
• hydroxychloroquine+penicillamine: Severe (increases risk of haematological toxicity)
• hydroxychloroquine+agalsidase alfa: Unknown (decreases effects)
• hydroxychloroquine+agalsidase beta: Unknown (decreases exposure)
• hydroxychloroquine+oral cholera vaccine: Unknown (decreases efficacy)
• live vaccines+hydroxy carbamide: Unknown (increases risk of generalised infection (possibly life-threatening))
• lanthanum+hydroxychloroquine: Unknown (decreases absorption)
• macrolides+hydroxychloroquine: Unknown (increases risk of serious cardiovascular adverse effects)
• hydroxychloroquine+remdesivir: Unknown (decreases effects)

Pregnancy

Safety in pregnancy has not been established. Use only if the potential benefit justifies the potential risk to the fetus.

Breast-feeding

Use with caution. Hydroxychloroquine is excreted in breast milk, and effects on the infant are unknown.

Storage

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

Formulations

• Tablets
• Oral solution

Indications

• Skin moisturization
• Cosmetic formulations
• Topical drug delivery systems

Dosage

Children: Paediatric dosing information must be based on specific product guidelines and formulations. Consult relevant resources for accurate dosing.

Adults: Dosage for adults varies based on formulation and intended use. Refer to specific product guidelines for dosing information.

Mechanism of action

Laury acts primarily as an emollient and surfactant. It helps to soften and smooth the skin by forming a barrier on the skin's surface, which helps to prevent moisture loss. Additionally, lauryl alcohol can enhance the penetration of other ingredients through the skin, thus improving the efficacy of topical formulations.

Pharmacodynamics

Laury exhibits hydrophobic properties due to its long hydrocarbon chain. As a fatty alcohol, it can interact with lipids in the skin, leading to improved hydration and skin barrier function. Its surfactant properties may also contribute to its ability to cleanse and solubilize other substances in formulations.

Pharmacokinetics

The pharmacokinetics of lauryl alcohol are not extensively studied. However, it is generally considered to have low systemic absorption when applied topically. It is primarily metabolized in the liver and excreted through urine, with minimal accumulation in body tissues.

Indications

• Acute poisoning
• Drug overdose
• Gastrointestinal disturbances
• Diarrhea
• Flatulence

Dosage

Children: Refer to specific product guidelines or consult a healthcare provider for appropriate dosage.

Adults: Refer to specific product guidelines or consult a healthcare provider for appropriate dosage.

Mechanism of action

Microcelac works primarily through physical adsorption. Activated charcoal has a high surface area which allows it to bind various substances, including drugs and toxins, in the gastrointestinal tract. This binding prevents their absorption into the systemic circulation, thereby facilitating their elimination through feces.

Pharmacodynamics

The pharmacodynamic profile of Microcelac is characterized by its ability to bind to various organic compounds and inorganic substances, reducing their bioavailability and effects. The extent of adsorption can vary based on the nature of the substance, the dose of activated charcoal, and the time elapsed since ingestion. It does not chemically alter the substances adsorbed, but effectively reduces their absorption and systemic effects.

Pharmacokinetics

Microcelac is not absorbed through the gastrointestinal tract; instead, it remains within the gut lumen where it exerts its effects by adsorbing toxins. The elimination of the drug occurs through feces, as the bound toxins and the unabsorbed drug are excreted following gastrointestinal transit.

Pregnancy

Safety during pregnancy has not been established; consult a healthcare provider before use.

Breast-feeding

Limited data available; a healthcare provider should be consulted before use while breastfeeding.

Storage

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

Indications

• Hyperthyroidism
• Graves' disease
• Thyroid storm

Dosage

Children: Refer to the BNF

Adults: The usual initial dose of propylthiouracil in adults is 300 mg per day, divided into 3 doses. The maintenance dose is typically 100-150 mg per day, adjusted based on thyroid function tests.

Mechanism of action

Propylthiouracil acts by inhibiting the enzyme thyroid peroxidase, which is involved in the iodination of tyrosine residues in thyroglobulin, a precursor of thyroid hormones. By blocking this enzyme, PTU reduces the production of thyroxine (T4) and triiodothyronine (T3), leading to decreased thyroid hormone levels in circulation. Additionally, PTU inhibits the conversion of T4 to T3 in peripheral tissues, further contributing to its antithyroid effects.

Pharmacodynamics

The pharmacodynamic effects of propylthiouracil are primarily centered around its ability to lower thyroid hormone levels, which helps alleviate symptoms of hyperthyroidism such as increased heart rate, weight loss, and anxiety. The onset of action can vary, but therapeutic effects may be observed within several weeks of initiation. Monitoring thyroid function tests is essential to assess the efficacy and adjust dosing as needed.

Pharmacokinetics

Propylthiouracil is well absorbed from the gastrointestinal tract, though its bioavailability can be affected by factors such as food intake. The drug is extensively metabolized in the liver, and its elimination half-life averages around 1-2 hours. Most of the drug is excreted in urine as metabolites. It is important to note that due to its rapid metabolism, multiple daily doses may be required to maintain therapeutic levels.

Interactions

• propylthiouracil+metyrapone: Severe (decreases effects)

Indications

• Dietary supplement
• Energy source
• Cosmetic ingredient
• Food additive

Dosage

Children: Refer to established dietary guidelines and consult nutritional resources for specific doses.

Adults: Refer to established dietary guidelines and consult nutritional resources for specific doses.

Mechanism of action

Stearic acid primarily acts as a source of energy. Once ingested, it undergoes beta-oxidation in the mitochondria, resulting in the production of acetyl-CoA, which enters the citric acid cycle to generate ATP. Stearic acid can also influence lipid metabolism and may impact cell membrane fluidity due to its role in phospholipid composition.

Pharmacodynamics

Stearic acid has a neutral effect on serum cholesterol levels compared to other saturated fatty acids. It does not raise low-density lipoprotein (LDL) cholesterol and may even have a beneficial effect on high-density lipoprotein (HDL) cholesterol levels. Its impact on metabolism includes promotion of lipogenesis and inhibition of lipolysis, contributing to energy homeostasis.

Pharmacokinetics

Stearic acid is absorbed in the gastrointestinal tract and transported via chylomicrons in the lymphatic system. It is metabolized primarily in the liver and muscle tissues. The half-life of stearic acid in the body varies depending on dietary intake and metabolic demands, and it is excreted as carbon dioxide and water through various metabolic pathways.

Pregnancy

Consult a healthcare professional before use, as safety during pregnancy is not established.

Breast-feeding

Consult a healthcare professional before use, as safety during breastfeeding is not established.

Storage

Store at room temperature, away from light and moisture.

Mechanism of action

Rosuvastatin is a statin medication and a competitive inhibitor of the enzyme HMG-CoA (3-hydroxy-3-methylglutaryl coenzyme A) reductase, which catalyzes the conversion of HMG-CoA to mevalonate, an early rate-limiting step in cholesterol biosynthesis. Rosuvastatin acts primarily in the liver, where decreased hepatic cholesterol concentrations stimulate the upregulation of hepatic low density lipoprotein (LDL) receptors which increases hepatic uptake of LDL. Rosuvastatin also inhibits hepatic synthesis of very low density lipoprotein (VLDL). The overall effect is a decrease in plasma LDL and VLDL. In vitro and in vivo animal studies also demonstrate that rosuvastatin exerts vasculoprotective effects independent of its lipid-lowering properties, also known as the pleiotropic effects of statins. This includes improvement in endothelial function, enhanced stability of atherosclerotic plaques, reduced oxidative stress and inflammation, and inhibition of the thrombogenic response. Statins have also been found to bind allosterically to β2 integrin function-associated antigen-1 (LFA-1), which plays an important role in leukocyte trafficking and in T cell activation. Rosuvastatin exerts an anti-inflammatory effect on rat mesenteric microvascular endothelium by attenuating leukocyte rolling, adherence and transmigration. The drug also modulates nitric oxide synthase (NOS) expression and reduces ischemic-reperfusion injuries in rat hearts. Rosuvastatin increases the bioavailability of nitric oxide by upregulating NOS and by increasing the stability of NOS through post-transcriptional polyadenylation. It is unclear as to how rosuvastatin brings about these effects though they may be due to decreased concentrations of mevalonic acid. Crestor is a selective and competitive inhibitor of HMG-CoA reductase, the rate-limiting enzyme that converts 3-hydroxy-3-methylglutaryl coenzyme A to mevalonate, a precursor of cholesterol. In vivo studies in animals, and in vitro studies in cultured animal and human cells have shown rosuvastatin to have a high uptake into, and selectivity for, action in the liver, the target organ for cholesterol lowering. In in vivo and in vitro studies, rosuvastatin produces its lipid-modifying effects in two ways. First, it increases the number of hepatic LDL receptors on the cell-surface to enhance uptake and catabolism of LDL. Second, rosuvastatin inhibits hepatic synthesis of VLDL, which reduces the total number of VLDL and LDL particles.

Pharmacodynamics

Rosuvastatin is a synthetic, enantiomerically pure antilipemic agent. It is used to lower total cholesterol, low density lipoprotein-cholesterol (LDL-C), apolipoprotein B (apoB), non-high density lipoprotein-cholesterol (non-HDL-C), and trigleride (TG) plasma concentrations while increasing HDL-C concentrations. High LDL-C, low HDL-C and high TG concentrations in the plasma are associated with increased risk of atherosclerosis and cardiovascular disease. The total cholesterol to HDL-C ratio is a strong predictor of coronary artery disease and high ratios are associated with higher risk of disease. Increased levels of HDL-C are associated with lower cardiovascular risk. By decreasing LDL-C and TG and increasing HDL-C, rosuvastatin reduces the risk of cardiovascular morbidity and mortality. Elevated cholesterol levels, and in particular, elevated low-density lipoprotein (LDL) levels, are an important risk factor for the development of CVD. Use of statins to target and reduce LDL levels has been shown in a number of landmark studies to significantly reduce the risk of development of CVD and all-cause mortality. Statins are considered a cost-effective treatment option for CVD due to their evidence of reducing all-cause mortality including fatal and non-fatal CVD as well as the need for surgical revascularization or angioplasty following a heart attack. Evidence has shown that even for low-risk individuals (with <10% risk of a major vascular event occurring within 5 years) statins cause a 20%-22% relative reduction in major cardiovascular events (heart attack, stroke, coronary revascularization, and coronary death) for every 1 mmol/L reduction in LDL without any significant side effects or risks. **Skeletal Muscle Effects** Cases of myopathy and rhabdomyolysis with acute renal failure secondary to myoglobinuria have been reported with HMG-CoA reductase inhibitors, including rosuvastatin. These risks can occur at any dose level, but are increased at the highest dose (40 mg). Rosuvastatin should be prescribed with caution in patients with predisposing factors for myopathy (e.g., age ≥ 65 years, inadequately treated hypothyroidism, renal impairment). The risk of myopathy during treatment with rosuvastatin may be increased with concurrent administration of some other lipid-lowering therapies (such as [fenofibrate] or [niacin]), [gemfibrozil], [cyclosporine], [atazanavir]/[ritonavir], [lopinavir]/ritonavir, or [simeprevir]. Cases of myopathy, including rhabdomyolysis, have been reported with HMG-CoA reductase inhibitors, including rosuvastatin, coadministered with [colchicine], and caution should therefore be exercised when prescribing these two medications together. Real-world data from observational studies has suggested that 10-15% of people taking statins may experience muscle aches at some point during treatment. **Liver Enzyme Abnormalities** Increases in serum transaminases have been reported with HMG-CoA reductase inhibitors, including rosuvastatin. In most cases, the elevations were transient and resolved or improved on continued therapy or after a brief interruption in therapy. There were two cases of jaundice, for which a relationship to rosuvastatin therapy could not be determined, which resolved after discontinuation of therapy. There were no cases of liver failure or irreversible liver disease in these trials. **Endocrine Effects** Increases in HbA1c and fasting serum glucose levels have been reported with HMG-CoA reductase inhibitors, including rosuvastatin calcium tablets. Based on clinical trial data with rosuvastatin, in some instances these increases may exceed the threshold for the diagnosis of diabetes mellitus. An in vitro study found that [atorvastatin], [pravastatin], [rosuvastatin], and [pitavastatin] exhibited a dose-dependent cytotoxic effect on human pancreas islet β cells, with reductions in cell viability of 32, 41, 34 and 29%, respectively, versus control]. Moreover, insulin secretion rates wer