Aspirin (Acetylsalicylic Acid) Dosage for Dogs

NSAID / Antiplatelet ⏱ Onset: 30-60 minutes ⏳ Duration: 12 hours

This dosage information is for educational purposes only. Always consult your veterinarian before giving any medication to your pet. Dosages may vary based on your pet's health conditions, other medications, and individual factors.

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Aspirin Dosage Chart for Dogs by Weight

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Weight	Low Dose	Standard Dose	Max Dose	Frequency
5 lbs (2.3 kg)	11.5mg	23mg	34.5mg	every 12 hours
10 lbs (4.5 kg)	22.5mg	45mg	67.5mg (81mg tablet)	every 12 hours
15 lbs (6.8 kg)	34mg	68mg (81mg tablet)	102mg	every 12 hours
20 lbs (9.1 kg)	45.5mg	91mg (81mg tablet)	136.5mg	every 12 hours
25 lbs (11.3 kg)	56.5mg	113mg	169.5mg (2 × 81mg)	every 12 hours
30 lbs (13.6 kg)	68mg (81mg tablet)	136mg	204mg	every 12 hours
40 lbs (18.1 kg)	90.5mg (81mg tablet)	181mg (2 × 81mg)	271.5mg	every 12 hours
50 lbs (22.7 kg)	113.5mg	227mg (3 × 81mg)	340.5mg (4 × 81mg)	every 12 hours
60 lbs (27.2 kg)	136mg	272mg	408mg (5 × 81mg)	every 12 hours
70 lbs (31.7 kg)	158.5mg (2 × 81mg)	317mg (4 × 81mg)	475.5mg (6 × 81mg)	every 12 hours
80 lbs (36.3 kg)	181.5mg (2 × 81mg)	363mg	544.5mg	every 12 hours
90 lbs (40.8 kg)	204mg	408mg (5 × 81mg)	612mg	every 12 hours
100 lbs (45.4 kg)	227mg (3 × 81mg)	454mg	681mg	every 12 hours
120 lbs (54.4 kg)	272mg	544mg	816mg (10 × 81mg)	every 12 hours
150 lbs (68 kg)	340mg (4 × 81mg)	680mg	1020mg	every 12 hours

What is Aspirin (Acetylsalicylic Acid) used for in dogs?

mild pain relief inflammation fever reduction blood clot prevention

How to give Aspirin to your dog

Always use buffered or enteric-coated aspirin to reduce stomach irritation. Give with food. Baby aspirin (81 mg) is often preferred for smaller dogs. Never give aspirin to cats without specific veterinary instruction, as cats metabolize salicylates very slowly.

Available Forms

tablet, buffered tablet

Give with Food?

Yes — give with food

Side effects of Aspirin in dogs

Common side effects

stomach upset

decreased appetite

vomiting

diarrhea

Serious side effects

gastrointestinal ulceration
bleeding disorders
kidney damage
liver toxicity

When to call the vet

Call your vet immediately if your dog shows any of these signs:

Vomiting or vomiting blood
Dark or tarry stools
Loss of appetite lasting more than 24 hours
Increased thirst or urination
Unusual bruising or bleeding

Frequently Asked Questions

Can I give my dog aspirin for pain?

Aspirin can be given to dogs for short-term pain relief, but it is not the safest NSAID choice. Veterinary-specific NSAIDs like carprofen or meloxicam are preferred for dogs because they have fewer gastrointestinal side effects. Always consult your vet before giving aspirin.

How much aspirin can I give my dog?

The typical dose is 5-10 mg per kilogram of body weight, given every 12 hours. For a 30 lb (14 kg) dog, this would be about one baby aspirin (81 mg). Always use the lowest effective dose and give with food.

Is baby aspirin safe for dogs?

Baby aspirin (81 mg) is commonly used for dogs due to its lower dose, which allows for more precise dosing in small to medium dogs. However, "safe" is relative — aspirin carries risks of GI ulceration even at low doses, so veterinary-specific NSAIDs are generally preferred.

Can I give my dog aspirin every day?

Daily aspirin use in dogs should only be done under veterinary supervision. Long-term use increases the risk of gastrointestinal ulceration, bleeding, and kidney problems. Your vet may prescribe daily low-dose aspirin for specific conditions like blood clot prevention.