Avas 20 mg

Description

Indications

Avas is prescribed alongside diet modification to help reduce elevated levels of total cholesterol, LDL cholesterol, apolipoprotein B (Apo-B), and triglycerides in patients who do not respond sufficiently to dietary changes or other non-drug treatments. The specific indications for Avas include:

• Familial Hypercholesterolemia (both heterozygous and homozygous types), for lowering total cholesterol and LDL cholesterol.
• Mixed Dyslipidemia (Fredrickson Types Ia and Ib), where cholesterol and triglyceride levels are elevated.
• Hypertriglyceridemia (Fredrickson Type IV), where serum triglycerides are high.
• Dysbetalipoproteinemia (Fredrickson Type III), for patients with abnormal lipid profiles.
• Coronary Artery Disease (CAD), to reduce the risk of ischemic heart events in patients with asymptomatic or mild to moderate symptomatic CAD and elevated LDL cholesterol levels.
• Hypercholesterolemia associated with diabetes or renal transplantation, to manage total and LDL cholesterol levels.

Always follow the advice of a registered healthcare provider when using this medication.

Pharmacology

Avas contains atorvastatin, a selective inhibitor of HMG-CoA reductase, the enzyme responsible for converting HMG-CoA to mevalonate, which is a precursor in cholesterol biosynthesis. By inhibiting this enzyme, atorvastatin reduces the synthesis of cholesterol in the liver. It also increases the number of LDL receptors in the liver, thereby improving the clearance of LDL cholesterol from the bloodstream.

• Absorption: After oral administration, atorvastatin is quickly absorbed, with maximum plasma concentrations occurring 1 to 2 hours after intake. The drug’s absorption increases with higher doses.
• Distribution: Atorvastatin is extensively bound to plasma proteins (98%), and its volume of distribution is about 381 liters.
• Metabolism: Atorvastatin is metabolized primarily by the liver through cytochrome P450 3A4, producing active metabolites that contribute to about 70% of the inhibitory activity against HMG-CoA reductase.
• Excretion: The drug and its metabolites are primarily excreted in bile. Less than 2% of atorvastatin is excreted in urine. The drug’s half-life is approximately 14 hours, with the inhibitory effect lasting 20-30 hours due to active metabolites.

Dosage & Administration

• For Primary Hypercholesterolemia and Combined Hyperlipidaemia:
  • Adults: Starting dose is usually 10 mg daily, which can be increased gradually up to a maximum of 80 mg per day.
  • Children (ages 10-18): Begin with 10 mg once daily, increasing as necessary to a maximum of 20 mg daily.
• For Familial Hypercholesterolemia:
  • Adults: Start with 10 mg daily, increasing to 40 mg after at least 4 weeks, with a maximum of 80 mg daily.
  • Children (ages 10-18): Begin with 10 mg daily, adjusting the dose as needed up to 80 mg daily.
• For Cardiovascular Event Prevention:
  • Adults: Begin with 10 mg daily and adjust based on response.

Patients should adhere to a cholesterol-lowering diet before starting Avas and continue the diet throughout treatment. The starting dose typically ranges from 10-20 mg, and the dose can be adjusted based on lipid levels. Regular monitoring (2-4 weeks) of lipid levels is required to assess the drug’s effectiveness and adjust the dosage if necessary.

Always follow the dosage instructions provided by your healthcare provider.

Interactions

Avas may interact with several other drugs, enhancing the risk of side effects. Notable interactions include:

• Cyclosporine, fibric acid derivatives, niacin, erythromycin, azole antifungals: These drugs may increase the risk of myopathy.
• Antacids: Reduce atorvastatin plasma concentration by approximately 35%, but LDL-C reduction is unaffected.
• Colestipol: Increases LDL-C reduction when coadministered with atorvastatin, despite a decrease in atorvastatin plasma concentration by 25%.
• Digoxin: Increases digoxin plasma concentration by approximately 20%.
• Erythromycin: Increases atorvastatin plasma concentration by 40%.
• Oral Contraceptives: May increase the plasma levels of norethindrone and ethinyl estradiol.
• Warfarin: Avas does not significantly affect prothrombin time in patients on chronic warfarin treatment.

Contraindications

Avas should not be used by individuals who are hypersensitive to atorvastatin or any of its components. It is contraindicated in patients with active liver disease or unexplained persistent elevations of serum transaminases. It is also not recommended for individuals with a history of severe reactions to other HMG-CoA reductase inhibitors.

Side Effects

Common side effects include:

• Gastrointestinal issues such as constipation, gas, dyspepsia, and abdominal discomfort.
• Other reported side effects include headache, back pain, fatigue, rash, muscle pain (myalgia), and joint pain (arthralgia).
  While side effects are generally mild, consult a healthcare provider if you experience any concerning symptoms.

Pregnancy & Lactation

• Pregnancy: Atorvastatin is contraindicated during pregnancy due to potential risks to the fetus. It should be discontinued if pregnancy is confirmed or suspected.
• Lactation: It is not known whether atorvastatin is excreted in human milk, but given its potential for serious side effects, it should not be used during breastfeeding.

Precautions & Warnings

• Liver Function: Liver function tests should be performed before starting treatment and periodically during treatment. Caution is required in patients with a history of liver disease or heavy alcohol use.
• Myopathy: If muscle pain, weakness, or tenderness occurs, patients should seek medical advice immediately. If CPK levels rise significantly, treatment should be stopped.
• Diabetes: Monitor blood sugar levels regularly, as atorvastatin may increase the risk of diabetes.

Use in Special Populations

• Elderly: Elderly patients may require lower doses due to altered drug metabolism.
• Renal Insufficiency: Avas does not require dose adjustments in patients with renal impairment.
• Hepatic Insufficiency: In patients with liver disease, plasma concentrations of Avas may be increased, so close monitoring is necessary.

Overdose Effects

There is no specific antidote for atorvastatin overdose. Treatment involves symptomatic care, monitoring liver function, and assessing serum CK levels. Hemodialysis is unlikely to significantly enhance atorvastatin clearance due to its strong plasma protein binding.

Therapeutic Class

• Statins, Other Anti-anginal & Anti-ischaemic drugs

Storage Conditions

Store at room temperature in a dry place, away from heat and direct light. Keep out of reach of children.

Chemical Structure

• Molecular Formula: C33H35FN2O5