Acute Coronary Syndrome (ACS): Clopidogrel tablets are indicated to reduce the risk of myocardial infarction (MI) and stroke in patients with non–ST-segment elevation ACS, including unstable angina (UA) and non–ST-elevation myocardial infarction (NSTEMI). It is also indicated for reducing the risk of MI and stroke in patients with acute ST-elevation myocardial infarction (STEMI).

Recent MI, Recent Stroke, or Established Peripheral Arterial Disease: Clopidogrel is indicated in patients with a history of recent MI or stroke, or in those with established peripheral arterial disease, to lower the risk of myocardial infarction and stroke.

Clopidogrel is a prodrug that works by inhibiting platelet activation and aggregation. Its active metabolite binds irreversibly to the P2Y12 subtype of ADP receptors on platelets, preventing platelet aggregation. Platelet inhibition begins within approximately 2 hours after a single oral dose. With repeated daily dosing of 75 mg, inhibition of ADP-induced platelet aggregation starts from the first day and reaches a steady-state effect between Day 3 and Day 7.

Acute Coronary Syndrome (ACS)

• Loading dose (for rapid effect): 300 mg (4 tablets) as a single oral dose
• Maintenance dose: 75 mg once daily, starting after the loading dose
• Note: Initiating treatment without a loading dose will delay the antiplatelet effect by several days.

2. Recent MI, Recent Stroke, or Established Peripheral Arterial Disease

• Dose: 75 mg once daily orally
• No loading dose is required in these patients.

Administration:

• Can be taken with or without food.

• NSAIDs, warfarin, SSRIs, and SNRIs: Concomitant use may increase the risk of bleeding.
• CYP2C19 inhibitors (e.g., omeprazole, esomeprazole): Concurrent use should be avoided as these may reduce the effectiveness of clopidogrel.
• Repaglinide (CYP2C8 substrates): Co-administration with clopidogrel should be avoided because it can increase plasma levels of repaglinide.

Clopidogrel is contraindicated in patients with known hypersensitivity to the drug or any of its components, and in those with active pathological bleeding such as peptic ulcer or intracranial hemorrhage.

Clopidogrel is generally well tolerated.
Common side effects: Bleeding, diarrhea, gastrointestinal discomfort, hemorrhage, and skin reactions.
Rare side effects: Acquired hemophilia, anemia, angioedema, arthralgia, arthritis, and bone marrow disorders.

There are no adequate and well-controlled studies in pregnant women. Clopidogrel should be used during pregnancy only if clearly necessary. It is not known whether clopidogrel is excreted in human milk. A decision should be made whether to discontinue breastfeeding or discontinue the drug, considering the importance of the medication to the mother.

• Clopidogrel is a prodrug, and its activation may be reduced in individuals with CYP2C19 genetic variations or when used with CYP2C19 inhibitors such as omeprazole or esomeprazole, potentially decreasing its effectiveness.
• Because it inhibits platelet function for the lifespan of platelets (7–10 days), the risk of bleeding is increased. Platelet transfusion may help restore clotting function.
• Discontinuation of clopidogrel increases the risk of cardiovascular events; however, it should be stopped at least 5 days before elective surgery to reduce bleeding risk and restarted as soon as hemostasis is achieved.
• Rare cases of thrombotic thrombocytopenic purpura (TTP) have been reported, which may require urgent treatment including plasma exchange.
• Hypersensitivity reactions such as rash, angioedema, or hematologic abnormalities may occur, especially in patients with a history of sensitivity to thienopyridines.

Safety and effectiveness in pediatric patients have not been established. No dosage adjustment is required in elderly patients.

Overdose of clopidogrel may result in bleeding complications. Platelet transfusion may help restore normal clotting function if needed.

Antiplatelet drugs

Store in a dry place at a temperature below 30°C. Protect from light. Do not freeze. Keep out of reach of children.