Home/Medicines/Aspirin (Acetylsalicylic Acid)
All medicines

Aspirin (Acetylsalicylic Acid)

NSAID / Antiplatelet Agent (Salicylate)
Last reviewed 21 Apr 2026 · PetCare.AI Editorial Team
Species
Dog, Cat
Brands
2 available
Interactions
6 documented
Formulations
3

Mechanism of action

Irreversibly acetylates and inactivates COX-1 and COX-2, reducing prostaglandin and thromboxane A2 synthesis. Low-dose aspirin inhibits platelet TXA2 production (antiplatelet) for life of platelet (~10 days in dogs).

At a glance

Class
NSAID / Antiplatelet Agent (Salicylate)
Schedule
OTC
Storage
Store at room temperature below 25°C, protect from moisture (hydrolysis to salicylic acid + acetic acid odor = degraded)

Dosing

🐕

Dog

Low-dose antiplatelet therapy for thromboembolic disorders (IMHA, cardiomyopathy
Dose
0.5–1 mg/kg
Route
PO
Frequency
q24h (antiplatelet); q8–12h (anti-inflammatory)
🐈

Cat

Cats lack hepatic glucuronidation — salicylate accumulates rapidly
Dose
5–10 mg/cat
Route
PO
Frequency
q48–72h MAXIMUM

Formulations

💊

Other — 3

Strength
—
Strength
—
Strength
—

Storage

Store at room temperature below 25°C, protect from moisture (hydrolysis to salicylic acid + acetic acid odor = degraded)

Safety

Monitoring parameters

GI signs (melena, vomiting)Renal functionPT/aPTT (coagulation)Salicylate levels if toxicity suspected

Interactions

Contraindicated — 4

Meloxicam
contraindicated
Two NSAIDs: additive COX inhibition causing severe GI ulceration, renal papillary necrosis, and platelet dysfunction.
Management: NEVER use two NSAIDs concurrently. Allow minimum 5-7 day washout (longer for aspirin due to irreversible platelet inhibition — 10 days).
Carprofen
contraindicated
Concurrent NSAIDs: synergistic GI and renal toxicity. Aspirin irreversibly inhibits platelets, compounding bleeding risk.
Management: NEVER combine. Washout 7-10 days from aspirin before starting any NSAID.
Deracoxib
contraindicated
Even COX-2 selective NSAID + aspirin causes significant GI ulceration — aspirin blocks COX-1 protective prostaglandins.
Management: Do not combine. 7-10 day washout from aspirin.
Etodolac
contraindicated
Two NSAIDs: additive COX inhibition, severe GI ulceration and renal injury.
Management: NEVER combine. 7-10 day washout from aspirin before any NSAID.

Major — 2

Prednisolone
major
Aspirin (irreversible COX inhibition + direct GI irritant) + corticosteroid: very high GI ulceration risk. Also, steroids increase aspirin clearance.
Management: Avoid concurrent use. If low-dose aspirin antiplatelet therapy needed with steroids, add omeprazole + misoprostol and monitor closely for melena.
Enoxaparin
major
Aspirin irreversibly inhibits platelet COX-1 (TXA2) + LMWH inhibits Factor Xa: marked additive bleeding risk.
Management: Extreme caution. Only combine under specialist guidance for specific thrombotic conditions (e.g., post-ATE in cats). Monitor bleeding closely.

Brands

Other markets

Bayer Aspirin
Bufferin

FAQs

Frequently asked questions

›What is Aspirin (Acetylsalicylic Acid)?
Aspirin (Acetylsalicylic Acid) is a nsaid / antiplatelet agent (salicylate) used in pets. Irreversibly acetylates and inactivates COX-1 and COX-2, reducing prostaglandin and thromboxane A2 synthesis. Low-dose aspirin inhibits platelet TXA2 production (antiplatelet) for life of platelet (~10 days in dogs).
›What is Aspirin (Acetylsalicylic Acid) used for in pets?
Aspirin (Acetylsalicylic Acid) is used in veterinary medicine for: Low-dose antiplatelet therapy for thromboembolic disorders (IMHA, cardiomyopathy; Cats lack hepatic glucuronidation — salicylate accumulates rapidly.
›What is the Aspirin (Acetylsalicylic Acid) dose for dogs?
For dogs, Aspirin (Acetylsalicylic Acid) is typically dosed as follows — Low-dose antiplatelet therapy for thromboembolic disorders (IMHA, cardiomyopathy: 0.5–1 mg/kg PO q24h (antiplatelet); q8–12h (anti-inflammatory). Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›What is the Aspirin (Acetylsalicylic Acid) dose for cats?
For cats, Aspirin (Acetylsalicylic Acid) is typically dosed as follows — Cats lack hepatic glucuronidation — salicylate accumulates rapidly: 5–10 mg/cat PO q48–72h MAXIMUM. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.
›Does Aspirin (Acetylsalicylic Acid) need a prescription?
Aspirin (Acetylsalicylic Acid) is available over the counter. Even so, you should consult your veterinarian before giving any medication to your pet.

References

CDSCO approvals (India) — 1

Aspirin Bolus Vet 6gm Bolus
M/s Alembic Limited · Approved 21.11.2005
for veterinary use
Source: CDSCO Veterinary Drug Approval Registry (1969–2026)

References

Textbooks & handbooks

  • Plumb, D.C. Plumb's Veterinary Drug Handbook. 10th ed., Wiley-Blackwell, 2023.
  • Vail, D.M., Thamm, D.H., & Liptak, J.M. (eds.). Withrow & MacEwen's Small Animal Clinical Oncology. 6th ed., Saunders/Elsevier, 2020.
  • Riviere, J.E., & Papich, M.G. (eds.). Veterinary Pharmacology and Therapeutics. 10th ed., Wiley-Blackwell, 2018.
  • National Research Council. Nutrient Requirements of Dogs and Cats. National Academies Press, Washington DC, 2006.
  • The Merck Veterinary Manual. Merck & Co., Online edition. https://www.merckvetmanual.com/

Clinical guidelines & consensus

  • Fletcher, D.J., Boller, M., Brainard, B.M., et al. "RECOVER Evidence and Knowledge Gap Analysis on Veterinary CPR." Journal of Veterinary Emergency and Critical Care, 2012;22(S1):S102–S131.
  • American Animal Hospital Association. 2018 AAHA Diabetes Management Guidelines for Dogs and Cats. AAHA Press.

Journals & peer-reviewed studies

  • Hogan, D.F., Fox, P.R., Jacob, K., et al. "Secondary prevention of cardiogenic arterial thromboembolism in the cat: The FAT CAT study." Journal of Veterinary Cardiology, 2015;17(Suppl 1):S306–S317.
  • Boswood, A., Häggström, J., Gordon, S.G., et al. "Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study — A Randomized Clinical Trial." Journal of Veterinary Internal Medicine, 2016;30(6):1765–1779.
  • ASPCA Animal Poison Control Center. Toxicology and Poison Management Guidelines. American Society for the Prevention of Cruelty to Animals. https://www.aspca.org/pet-care/animal-poison-control

Regulatory & approvals

  • Central Drugs Standard Control Organisation (CDSCO), Government of India. Veterinary Drug Approval Registry, 1969–2026. Directorate General of Health Services. https://cdsco.gov.in/

Databases

  • Washington State University, College of Veterinary Medicine. Veterinary Clinical Pharmacology Laboratory (VCPL) — MDR1 Multidrug Sensitivity Database. https://vcpl.vetmed.wsu.edu/
Educational reference only
This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet. Find a vet near you →