TCL-R 10mg Tablet 1 Strip

✔️ Pharmacology

Atorvastatin is a selective inhibitor of the enzyme HMG-CoA reductase, which plays a key role in converting HMG-CoA into mevalonate, a precursor required for cholesterol synthesis. By inhibiting this enzyme, atorvastatin reduces cholesterol production in the liver and lowers circulating cholesterol and lipoprotein levels. It also increases the number of LDL receptors on liver cells, enhancing the removal and breakdown of LDL cholesterol from the bloodstream.

Absorption: Atorvastatin is rapidly absorbed after oral administration, reaching peak plasma concentrations within 1–2 hours. Its absorption increases proportionally with the administered dose. The absolute bioavailability of the parent drug is approximately 14%, while the systemic availability of HMG-CoA reductase inhibitory activity is about 30%.

Distribution: The mean volume of distribution is approximately 381 litres, and about 98% of atorvastatin binds to plasma proteins. Its blood-to-plasma ratio of approximately 0.25 indicates limited penetration into red blood cells. Animal studies suggest that atorvastatin may also be secreted into breast milk in humans.

Metabolism: Atorvastatin undergoes extensive metabolism into ortho-hydroxylated and para-hydroxylated derivatives, along with several beta-oxidation products. These active metabolites contribute substantially to its cholesterol-lowering action, accounting for approximately 70% of circulating HMG-CoA reductase inhibitory activity. The enzyme CYP3A4 plays an important role in its metabolism, which explains why medicines such as erythromycin can increase atorvastatin concentrations. In animals, the ortho-hydroxy metabolite undergoes further glucuronidation.

Excretion: Atorvastatin and its metabolites are eliminated mainly through bile following hepatic and extrahepatic metabolism. The drug does not appear to undergo significant enterohepatic recirculation. Its average plasma elimination half-life is approximately 14 hours, while the inhibitory activity persists for 20–30 hours due to active metabolites. Less than 2% of an oral dose is excreted in urine.

✔️ Dosage & Administration

Geriatric patients: In healthy adults aged 65 years and older, atorvastatin plasma concentrations may be approximately 40% higher for peak concentration (Cmax) and 30% higher for overall exposure (AUC) than in younger adults. Older patients may experience a greater LDL cholesterol reduction at the same dose.

Pediatric patients: Pharmacokinetic information in children is limited. Use in children should follow approved age-specific indications, dosage recommendations, and specialist advice.

Gender: No clinically significant difference in LDL cholesterol reduction has been observed between men and women.

Renal impairment: Kidney disease generally does not significantly affect atorvastatin plasma concentrations or its LDL cholesterol-lowering effect. Dose adjustment is usually unnecessary in patients with renal impairment.

Hemodialysis: Hemodialysis is not expected to substantially increase atorvastatin clearance because the drug is extensively bound to plasma proteins.

Hepatic impairment: Atorvastatin concentrations may increase substantially in patients with chronic alcoholic liver disease. It should not be used in patients with active liver disease or unexplained persistent transaminase elevations.

✔️ Interaction

• TCL-R may interact with other medicines, potentially affecting its safety or cholesterol-lowering effect.
• Cyclosporine, fibrates, niacin, erythromycin, and azole antifungals: Concomitant use may increase the risk of myopathy and muscle-related complications.
• Antacids: Antacid suspensions may reduce atorvastatin plasma concentrations by approximately 35%, although the reduction in LDL cholesterol may remain unchanged.
• Colestipol: May lower atorvastatin plasma concentrations by approximately 25%. However, the combination may produce a greater reduction in LDL cholesterol than either medicine alone.
• Digoxin: Concurrent administration may increase steady-state digoxin concentrations by approximately 20%. Appropriate monitoring is recommended.
• Erythromycin: May increase atorvastatin plasma concentrations by approximately 40% through inhibition of CYP3A4.
• Oral contraceptives: Atorvastatin may increase the exposure to norethindrone and ethinyl estradiol by approximately 30% and 20%, respectively. These effects should be considered when selecting an oral contraceptive.
• Warfarin: TCL-R has not shown a clinically significant effect on prothrombin time in patients receiving long-term warfarin therapy. Monitoring may still be appropriate when treatment is initiated or adjusted.

✔️ Side Effects:

• Constipation
• Flatulence
• Indigestion (dyspepsia)
• Abdominal pain
• Headache
• Back pain
• Skin rash
• Weakness or fatigue (asthenia)
• Joint pain (arthralgia)
• Muscle pain (myalgia)
• Infections

✔️ TCL-R should not be used in patients who:

• Have a known hypersensitivity to atorvastatin or any component of the formulation.
• Have active liver disease or unexplained, persistent elevations in serum transaminase levels.
• Have previously experienced a serious adverse reaction to an HMG-CoA reductase inhibitor.

✔️ Pregnancy & Lactation

Pregnancy: Atorvastatin is contraindicated during pregnancy because its safety has not been established in pregnant women. Animal studies have shown reproductive toxicity, and cholesterol synthesis is important for fetal development. Women who are pregnant, planning to become pregnant, or suspect they may be pregnant should not use atorvastatin. Treatment should be discontinued if pregnancy occurs, under medical guidance.

Lactation: It is unknown whether atorvastatin or its metabolites pass into human breast milk. Animal studies have demonstrated the presence of the drug and its active metabolites in milk. Because of the potential risk of serious adverse effects in infants, atorvastatin is contraindicated during breastfeeding.

✔️ Precautions & Warnings

• Liver function: Liver function tests should be performed before treatment begins and periodically during therapy when clinically indicated.
• Alcohol consumption: Use with caution in patients who consume substantial amounts of alcohol or have a history of liver disease.
• Muscle complications: If myopathy is suspected or diagnosed, or creatine phosphokinase (CPK) levels become markedly elevated, treatment should be discontinued or reassessed by the treating physician.
• Diet and lifestyle: Continue the prescribed cholesterol-lowering diet and recommended lifestyle measures during treatment.
• Drug interactions: Inform the physician about all prescription medicines, over-the-counter products, and supplements being taken.

✔️ Storage Conditions

Store in a dry place, protected from light and heat. Keep out of the reach of children.