PupkeeperToxicEmergency
Dog ate decongestants (pseudoephedrine, phenylephrine)? What to do
Decongestants like pseudoephedrine can overstimulate dogs, causing agitation, a racing heart, high blood pressure, tremors and high temperature.
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, Australia, Canada, New Zealand
What to do now
- Call your vet or a pet poison line now.
- Keep the packaging and bring it with you.
- Read the label for other drugs, such as pain relievers, and tell the vet.
Don't
- Don't make your dog vomit unless a vet tells you to.
Signs to watch for
- Agitation or hyperactivity
- Big pupils
- Fast heart rate
- Tremors
- High body temperature
- Head bobbing or hiding
- Vomiting
Why
In an overdose, decongestants squeeze major blood vessels, which can cause dangerous high blood pressure and stroke. They are often hidden in cold, flu and allergy combination products.
Sources
- Pet Poison Helpline: Decongestants
- Merck Veterinary Manual: Toxicoses in Animals From Human Cold and Allergy Medications
- Merck Veterinary Manual: Poisoning from Human Over-the-Counter Drugs
Guide reviewed 9 October 2026.
General information from the sources above, not a diagnosis. When in doubt, call your vet.