ANACLOP 75 TABLET

Indications

• Acute coronary syndrome (ACS)
• Myocardial infarction (MI)
• Peripheral arterial disease (PAD)
• Ischemic stroke prevention
• Post-stenting to prevent thrombosis

Dosage

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

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

Mechanism of action

Clopidogrel is a prodrug that requires metabolic activation to exert its effects. It is metabolized in the liver to its active thiol metabolite, which irreversibly binds to the P2Y12 ADP receptor on platelets. This binding inhibits the activation of the glycoprotein IIb/IIIa complex, which is essential for platelet aggregation, thus reducing the ability of platelets to clump together and form clots.

Pharmacodynamics

The antiplatelet effect of clopidogrel begins within a few hours after administration, with peak effects occurring approximately 3 to 7 days after initiation of therapy. Its antiplatelet activity can last for several days due to the irreversible binding of the active metabolite to the P2Y12 receptor. This prolonged action requires discontinuation of the drug several days prior to surgical procedures to minimize bleeding risk.

Pharmacokinetics

Clopidogrel is rapidly absorbed after oral administration, with peak plasma concentrations occurring in about 1 to 2 hours. It undergoes extensive hepatic metabolism, primarily by cytochrome P450 enzymes, specifically CYP2C19, to form its active metabolite. The elimination half-life of the active metabolite is short, approximately 30 minutes, but the antiplatelet effect lasts much longer due to the irreversible binding to platelets. Clopidogrel and its metabolites are primarily excreted in urine and feces.

Contra-indications

• Active bleeding such as peptic ulcer or intracranial hemorrhage
• Severe liver impairment
• Hypersensitivity to clopidogrel or any of its components

Adverse effects

• Bleeding complications including gastrointestinal bleeding and hemorrhagic stroke
• Thrombocytopenia
• Rash or pruritus
• Diarrhea
• Abdominal pain
• Nausea
• Headache

Interactions

• Concurrent use with anticoagulants may increase the risk of bleeding
• NSAIDs may increase the risk of gastrointestinal bleeding
• Proton pump inhibitors (especially omeprazole) can reduce the antiplatelet effect of clopidogrel
• Certain CYP2C19 inhibitors (e.g., fluoxetine, ticlopidine) may affect clopidogrel metabolism

Precautions

• Use with caution in patients with a history of bleeding disorders
• Monitor for signs of bleeding during therapy
• Discontinue prior to any surgical procedure to minimize bleeding risk
• Consider alternative antiplatelet therapy in patients with poor CYP2C19 metabolism

Pregnancy

Clopidogrel should only be used during pregnancy if clearly needed, as it is categorized under FDA pregnancy category B, indicating that animal reproduction studies have failed to demonstrate a risk to the fetus.

Breast-feeding

Clopidogrel is excreted in breast milk, caution is advised when administering to nursing mothers.

Storage

Store at room temperature, away from moisture and heat. Keep the medication in its original container.

Formulations

• Tablets: 75 mg, 300 mg