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Antiplatelet (P2Y12 Inhibitor) Pregnancy: Avoid — limited data

Clopidogrel (Stroke/TIA Secondary Prevention)

Brand names: Plavix

Adult dose

Dose: Secondary prevention (stroke/TIA): 75 mg OD. Acute TIA/minor stroke (DAPT): clopidogrel 300 mg loading, then 75 mg OD + aspirin 75 mg for 21 days, then clopidogrel 75 mg OD monotherapy
Route: Oral
Frequency: Once daily
Max: 75 mg/day (maintenance)
CAPRIE trial: clopidogrel superior to aspirin for secondary prevention of stroke, MI, or vascular death. CHANCE/POINT trials: DAPT (dual antiplatelet, clopidogrel + aspirin) for 21 days after TIA/minor stroke reduces early recurrent stroke without excess bleeding.

Paediatric dose

Route: N/A
Frequency: N/A
Max: Not licensed in children
Not established in paediatric patients

Dose adjustments

Renal

No dose adjustment required

Hepatic

Avoid in severe hepatic impairment (bleeding risk)

Clinical pearls

  • NICE NG128: clopidogrel first-line antiplatelet for secondary prevention after ischaemic stroke/TIA (superior to aspirin)
  • DAPT after TIA/minor stroke: 21-day course of clopidogrel + aspirin (CHANCE trial: 32% relative risk reduction in 90-day stroke recurrence)
  • CYP2C19 polymorphism: poor metabolisers have reduced antiplatelet effect — relevant if therapeutic failure; check genetic testing in selected patients
  • PPI choice: if GI protection needed, use pantoprazole not omeprazole (less CYP2C19 inhibition)

Contraindications

  • Active pathological bleeding
  • Severe hepatic impairment
  • Breastfeeding

Side effects

  • Bleeding (GI, intracranial)
  • GI upset
  • Rash
  • Thrombotic thrombocytopenic purpura (TTP — rare)
  • Neutropenia (rare)

Interactions

  • Omeprazole — CYP2C19 interaction reduces antiplatelet effect (use pantoprazole instead)
  • NSAIDs — increased bleeding risk
  • Warfarin/DOACs — triple therapy (anticoagulant + 2 antiplatelets): significant bleeding risk

Monitoring

  • Signs of bleeding
  • GI symptoms
  • Haematology if TTP suspected (falling platelets + CNS symptoms)
  • Adherence

Reference: BNFc; BNF; CAPRIE Trial (Lancet 1996); CHANCE Trial (Wang et al, NEJM 2013); NICE NG128. Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

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