PupkeeperCaution
Dog ate non-drowsy allergy pills (cetirizine, loratadine)? Caution: what to do now
Caution. An overdose of non-drowsy allergy pills is usually low risk for dogs, but pills that also contain a decongestant can be dangerous.
If your dog ate or touched this, call your vet or a pet poison line now
United States
Poison lines in other countries: United Kingdom, Canada, Australia, New Zealand, Belgium, France, JM, PR, Singapore, Switzerland, TT, VI
Non-drowsy allergy pills (cetirizine, loratadine) and dogs: key facts
- Verdict
- Caution · Call your vet or a poison line
- What it can do
- Sleepiness or low energy, hyperactivity, vomiting or stomach upset and drooling.
- How fast
- Within 5 hours
- What to do now
- Call your vet or a pet poison line now. All steps
- Sources
- Merck Veterinary Manual, VCA Animal Hospitals, Pet Poison Helpline. Reviewed 9 October 2026.
What should I do if my dog ate non-drowsy allergy pills (cetirizine, loratadine)?
- Call your vet or a pet poison line now.
- Check the box for a D after the name, or a decongestant such as pseudoephedrine, and tell the vet.
- Keep the packaging and bring it with you.
Don't
- Don't make your dog vomit unless a vet tells you to.
- Never give your dog an allergy pill that also contains a decongestant.
Symptoms to watch for
- Sleepiness or low energy
- Hyperactivity
- Vomiting or stomach upset
- Drooling
When signs appear: Within 5 hours
Why
Cetirizine, loratadine and fexofenadine are newer antihistamines that are thought not to affect the brain at normal doses, though an overdose can. Allergy pills with a D after the name also contain a decongestant, which makes poisoning more serious.
Sources
- Merck Veterinary Manual: Toxicoses in Animals From Human Cold and Allergy Medications
- VCA Animal Hospitals: Cetirizine
- Pet Poison Helpline: Decongestants
Guide reviewed 9 October 2026. Page updated 7 November 2026.
General information from the sources above, not a diagnosis. When in doubt, call your vet.