Pet Safety / Compounds / Clopidogrel

Is Clopidogrel safe for dogs and cats?

Low risk for pets

(Dogs-specific data is limited; this page draws from cat context.) Clopidogrel is the standard of care antiplatelet therapy for cats with hypertrophic cardiomyopathy (HCM) at high risk of aortic thromboembolism (ATE) — a devastating complication causing acute hind-limb paralysis ('saddle thrombus') with ~50% mortality or euthanasia at presentation. FATCAT trial: the landmark veterinary clinical trial (Boswood et al.) showed clopidogrel superior to aspirin for prevention of ATE in cats with HCM; clopidogrel 18.75 mg once daily reduced ATE recurrence and improved survival. Feline dosing: 18.75 mg (one-quarter of a 75 mg tablet) once daily; many pharmacies compound clopidogrel at lower concentrations for cats. Aortic thromboembolism: occurs in cats with left atrial enlargement from HCM — thrombus forms in dilated left atrium, embolizes to aortic bifurcation; sudden onset of hind-limb paresis, cold limbs, absent femoral pulses, severe pain; emergency veterinary care required. CYP2C19 in cats: feline hepatic CYP enzyme profile differs from humans — the clinical relevance of feline CYP2C19 polymorphisms for clopidogrel activation is less well characterized but efficacy data from FATCAT support adequate activation in most cats. Side effects in cats: generally well-tolerated at 18.75 mg; rare GI signs; bleeding risk with concurrent trauma or surgery.

What is clopidogrel?

The IUPAC name is methyl (2S)-2-(2-chlorophenyl)-2-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)acetate.

Also known as: methyl (2S)-2-(2-chlorophenyl)-2-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)acetate, Zyllt, Thrombo, (+)-Clopidogrel.

IUPAC name: methyl (2S)-2-(2-chlorophenyl)-2-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)acetate
CAS number: 113665-84-2
Molecular formula: C16H16ClNO2S
Molecular weight: 321.8 g/mol
SMILES: COC(=O)C(C1=CC=CC=C1Cl)N2CCC3=C(C2)C=CS3
PubChem CID: 60606

Risk for dogs

Low risk

Clopidogrel is the standard of care antiplatelet therapy for cats with hypertrophic cardiomyopathy (HCM) at high risk of aortic thromboembolism (ATE) — a devastating complication causing acute hind-limb paralysis ('saddle thrombus') with ~50% mortality or euthanasia at presentation. FATCAT trial: the landmark veterinary clinical trial (Boswood et al.) showed clopidogrel superior to aspirin for prevention of ATE in cats with HCM; clopidogrel 18.75 mg once daily reduced ATE recurrence and improved survival. Feline dosing: 18.75 mg (one-quarter of a 75 mg tablet) once daily; many pharmacies compound clopidogrel at lower concentrations for cats. Aortic thromboembolism: occurs in cats with left atrial enlargement from HCM — thrombus forms in dilated left atrium, embolizes to aortic bifurcation; sudden onset of hind-limb paresis, cold limbs, absent femoral pulses, severe pain; emergency veterinary care required. CYP2C19 in cats: feline hepatic CYP enzyme profile differs from humans — the clinical relevance of feline CYP2C19 polymorphisms for clopidogrel activation is less well characterized but efficacy data from FATCAT support adequate activation in most cats. Side effects in cats: generally well-tolerated at 18.75 mg; rare GI signs; bleeding risk with concurrent trauma or surgery.

Risk for cats

Low risk

Regulatory consensus

1 regulatory bodyhas classified Clopidogrel.

Agency	Year	Classification	Notes
FDA	2010	Black Box Warning	Reduced efficacy in CYP2C19 poor metabolizers

Regulators apply different standards of evidence — animal-data weighting, exposure-pattern assumptions, epidemiological power thresholds — which is why two scientific bodies can review the same data and reach different conclusions. The disagreement is the data.

Where pets encounter clopidogrel

Industrial Facilities — Manufacturing plants, Chemical storage areas, Waste treatment sites
Occupational Environments — Factories, Warehouses, Transportation vehicles

Safer alternatives

Lower-risk approaches that achieve a similar outcome to Clopidogrel:

Alternative drug class; Non-pharmacological therapy; Lowest effective dose
Trade-offs: Direct chemical substitution requires verification that the replacement does not introduce new hazards (regrettable substitution). Conduct full hazard assessment of proposed alternative before adoption.

Relative cost: 1.2-2×

Frequently asked questions

What products contain clopidogrel?

Clopidogrel appears in: Manufacturing plants (Industrial facilities); Chemical storage areas (Industrial facilities); Factories (Occupational environments); Warehouses (Occupational environments).

See Clopidogrel in the pets app

Look up products containing clopidogrel, compare to alternatives, and explore the full data record.

Open in pets View raw API data

Sources (2)

FDA Prescribing Information: Clopidogrel (Plavix) — P2Y12 antiplatelet; CYP2C19 Black Box prodrug activation; PPI interaction; DAPT stent thrombosis; no reversal agent; platelet transfusion; prasugrel/ticagrelor alternatives; FATCAT veterinary feline HCM trial (2023) (2023) — regulatory
ASPCA Animal Poison Control Center: Cardiac Drug Toxicosis in Pets — statin myopathy in cats; beta-blocker bradycardia dogs; CCB toxicity (amlodipine/diltiazem); ACE inhibitor renal effects; warfarin anticoagulant; furosemide; toxic dose thresholds (2023) (2023) — veterinary

Reference data, not professional advice. Aggregates publicly available regulatory and scientific data; not a substitute for veterinary, medical, legal, or regulatory advice. Why we built ALETHEIA →