Veterinary drug · Drug monograph

Clopidogrel: veterinary dose and monograph

Clopidogrel is a veterinary drug. Thienopyridine antiplatelet agent — irreversibly blocks the platelet P2Y12 ADP receptor, reducing platelet aggregation. Indications include feline arterial thromboembolism prophylaxis (cardiomyopathy, atrial enlargement); canine thromboprophylaxis (IMHA, PLN, hypercoagulable states). This monograph lists 3 reference doses for dogs, cats and horses, each with route, frequency and source.

At a glance

Drug class: Veterinary drug
Also known as: Plavix
Species with doses: Dogs, Cats and Horses
General dose range: 1–4 mg/kg PO q24h — check the species tables for the indication
Routes: PO
Last reviewed: 1 October 2026

Indications

Feline arterial thromboembolism prophylaxis (cardiomyopathy, atrial enlargement)
Canine thromboprophylaxis (IMHA, PLN, hypercoagulable states)

Clopidogrel dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

Clopidogrel doses for dogs
Indication	Dose	Route	Frequency	Duration
Thromboprophylaxis (IMHA / PLN)	1–3 mg/kg	PO	q24h	—

Thromboprophylaxis (IMHA / PLN): Papich 5e: 2 mg/kg q24h PO; an oral loading dose of 2–4 mg/kg (occasionally 10 mg/kg) followed by 1–2 mg/kg q24h. Plumb’s p.303 (Brainard 2008): 1–3 mg/kg PO once daily, or 0.5–1 mg/kg when combined with aspirin.

Cats

Clopidogrel doses for cats
Indication	Dose	Route	Frequency	Duration
Arterial thromboembolism prophylaxis	18.75 mg/cat	PO	q24h	—

Arterial thromboembolism prophylaxis: Papich 5e and Plumb’s p.303 (Hogan 2006): 18.75 mg per cat (¼ of a 75 mg tablet) once daily; bitter — put fragments in gelatin capsules or give with food. Plumb’s also lists 1–3 mg/kg once daily, or 0.5–1 mg/kg with aspirin (Brainard 2008).

Horses

Clopidogrel doses for horses
Indication	Dose	Route	Frequency	Duration
Antiplatelet therapy	2–4 mg/kg	PO	load 4 mg/kg, then 2 mg/kg q24h	—

Antiplatelet therapy: Papich 5e: horses — loading dose 4 mg/kg followed by 2 mg/kg q24h PO.

Contraindications

Active haemorrhage. Discontinue ~5–7 days before elective surgery (irreversible platelet effect). Caution with other antithrombotics / NSAIDs (additive bleeding).

Adverse effects

Bleeding / bruising (usually mild)
Vomiting, inappetence; bitter taste (hypersalivation in cats)

Drug interactions

NSAIDs / aspirin / other antiplatelets / anticoagulants: additive bleeding risk
Proton-pump inhibitors (omeprazole): may reduce conversion to the active metabolite (significance less defined in cats)
Strong CYP2C19 / CYP3A modulators: altered activation of the prodrug

Pregnancy and lactation

Safety not established in pregnancy / lactation — avoid unless clearly indicated.

Monitoring

Signs of bleeding / bruising; PCV if haemorrhage suspected
Discontinue 5–7 days before elective surgery
Limb perfusion / femoral pulses in at-risk cardiomyopathy cats

Toxicity and overdose

Overdose prolongs bleeding time; spontaneous or trauma-related haemorrhage is the principal risk.

Management: No specific antidote and the platelet effect is irreversible — platelet transfusion is required for serious bleeding. Otherwise supportive: control haemorrhage, IV fluids, monitor PCV.

Clinical pearls

First-line over aspirin for the at-risk cardiomyopathy cat — the FAT CAT trial showed longer time to thromboembolism / death
Quarter-tablet dosing is bitter — give in food or a gel cap to avoid hypersalivation and refusal
Stop 5–7 days before elective surgery; the platelet inhibition is irreversible for the platelet’s lifespan

Mechanism of action

Thienopyridine prodrug. Its active metabolite irreversibly blocks the platelet P2Y12 ADP receptor, preventing ADP-mediated activation of the GPIIb/IIIa complex and thus platelet aggregation for the platelet’s ~7–10-day lifespan.

Formulations and products

Clopidogrel 75 mg tablet
Plavix — 75 mg, Tablet (human-label)
Clopilet — 75 / 150 mg, Tablet (human-label)
Deplatt — 75 / 150 mg, Tablet (human-label)

Storage

Store at 15–30 °C, dry.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Frequently asked questions

What is the dose of Clopidogrel for dogs?

Reference doses for Clopidogrel in dogs: 1–3 mg/kg PO q24h (Thromboprophylaxis (IMHA / PLN)). Confirm against the label and the patient before use.

What is the dose of Clopidogrel for cats?

Reference doses for Clopidogrel in cats: 18.75 mg/cat PO q24h (Arterial thromboembolism prophylaxis). Confirm against the label and the patient before use.

What is the dose of Clopidogrel for horses?

Reference doses for Clopidogrel in horses: 2–4 mg/kg PO load 4 mg/kg, then 2 mg/kg q24h (Antiplatelet therapy). Confirm against the label and the patient before use.

When should Clopidogrel not be used?