Aspirin
Also known as: ASA, Bayer, Ecotrin, Bufferin, Ascriptin, Alka-Seltzer, Empirin, Halfprin, Aspirin BP
- **Watch for Bleeding:** Contact your veterinarian immediately if you notice signs of stomach ulcers or bleeding, such as black, tarry stools, vomit that looks like coffee grounds, loss of appetite, or severe lethargy. - **Strict Dosing:** Never give more aspirin than prescribed, and never give it more frequently. This is especially critical for **cats**, as they process aspirin very slowly and can easily be fatally poisoned by standard human doses. - **Food Animal Withdrawal:** While there are no official FDA withdrawal times, a minimum of 1 day withdrawal for milk or meat is recommended to protect salicylate-sensitive individuals.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- For analgesia
- As an antiinflammatory/antirheumatic
- For antipyrexia
- Post-Adulticide therapy for heartworm disease
- For adjunctive therapy in IMHA (antithrombotic)
- For adjunctive therapy of glomerular disease (antithrombotic)
- For adjunctive therapy with azathioprine and glucocorticoids for immune-mediated hemolytic anemia
- As an analgesic/antiinflammatory prior to elective intraocular surgery
- Reduction of platelet aggregation (e.g. IMHA)
- Analgesia, pyrexia, inflammation
- General use
- General use
- For analgesia/antipyrexia/antiinflammatory
How it is given
Possible side effects
- Gastric irritation (nausea, anorexia, vomiting)
- Gastrointestinal ulceration and occult blood loss
- Secondary anemia or hypoproteinemia (due to chronic GI blood loss)
- Metabolic acidosis (especially in cats)
- Hypersensitivity reactions (rare in dogs)
Cautions & contraindications
- Known hypersensitivity to salicylates
- Active gastrointestinal bleeding or ulcers
- Bleeding disorders (relative contraindication)
- Asthma (relative contraindication)
- Renal insufficiency (relative contraindication)
- Pregnancy (especially later stages; low-grade teratogen and may delay labor)
- **Hepatic and Renal Function:** Use with extreme caution and enhanced monitoring in patients with severe hepatic failure or diminished renal function. **Hypoalbuminemia:** Because aspirin is highly protein-bound, patients with low albumin may require lower dosages to prevent toxicity from increased free drug levels. **Surgical Procedures:** Due to irreversible platelet inhibition, aspirin therapy should ideally be halted one week prior to elective surgical procedures to prevent excessive bleeding. **Species Specifics:** Must be used with extreme caution in **cats** due to their inability to rapidly metabolize salicylates. Use cautiously in **neonatal animals**, as adult doses may lead to toxicity.
Drug interactions
- Alkalinizing drugs (e.g., sodium bicarbonate, acetazolamide): Significantly increases the renal excretion of salicylates; carbonic anhydrase inhibitors may cause systemic acidosis and increase CNS salicylate levels, leading to toxicity.
- Aminoglycosides: May increase the likelihood of nephrotoxicity.
- Corticosteroids: May increase salicylate clearance (decreasing serum levels) and significantly increase the risk of gastrointestinal ulceration and bleeding.
- Digoxin: Aspirin may increase plasma levels of digoxin by decreasing its clearance.
- Furosemide: May compete with renal excretion of aspirin, delaying its elimination and potentially causing toxicity at high doses.
- Heparin or Oral Anticoagulants: Increased risk of bleeding due to synergistic antiplatelet/anticoagulant effects.
- Methotrexate: Aspirin may displace methotrexate from plasma proteins, increasing the risk of methotrexate toxicity.
- Other NSAIDs: Increased risk of severe GI ulceration. A washout period of 3-10 days is recommended when switching from aspirin to a COX-2 selective NSAID.
- Phenobarbital: May increase the rate of aspirin metabolism by inducing hepatic enzymes.
Frequently asked questions
What is Aspirin used for in pets?
- **Watch for Bleeding:** Contact your veterinarian immediately if you notice signs of stomach ulcers or bleeding, such as black, tarry stools, vomit that looks like coffee grounds, loss of appetite, or severe lethargy. - **Strict Dosing:** Never give more aspirin than prescribed, and never give it more frequently. This is especially critical for **cats**, as they process aspirin very slowly and can easily be fatally poisoned by standard human doses. - **Food Animal Withdrawal:** While there are no official FDA withdrawal times, a minimum of 1 day withdrawal for milk or meat is recommended to protect salicylate-sensitive individuals.
Is Aspirin safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
Worried about your pet?
Peqaboo’s AI helps you track symptoms, understand lab reports, and know when to see a vet.
Get the Peqaboo app