TreatorToxic

Is Pseudoephedrine (Sudafed) toxic to dogs or cats?

Category: Medication | Last reviewed: June 2026

Quick verdict

Dogs

TOXIC

Cats

TOXIC

Pseudoephedrine (Sudafed) and dogs

TOXIC
Severity: High

Pseudoephedrine is a stimulant (sympathomimetic) with a narrow margin of safety in pets. Clinical signs can appear at 5-6 mg/kg, and doses around 10-12 mg/kg can be fatal. It causes a surge of agitation, racing heart, high blood pressure and dangerous overheating. Many cold and flu products combine it with acetaminophen, adding separate liver toxicity.

Onset

30-60 minutes; delayed and prolonged with extended-release products

Symptoms

  • - hyperactivity
  • - agitation
  • - rapid heart rate
  • - high blood pressure
  • - dilated pupils
  • - tremors
  • - vomiting
  • - overheating
  • - seizures

What to do now

Contact ASPCA Poison Control (888-426-4435) or your vet immediately. Bring the packaging and note whether it is an extended-release product.

Toxicity is dose-dependent. Your dog's weight and the quantity consumed are both important - include these when you call poison control.

Pseudoephedrine (Sudafed) and cats

TOXIC
Severity: High

Cats are highly sensitive to stimulants. The same narrow toxic range applies, and combination cold-and-flu products containing acetaminophen are catastrophic for cats, which cannot metabolise acetaminophen.

Onset

30-60 minutes

Symptoms

  • - agitation
  • - rapid heart rate
  • - high blood pressure
  • - dilated pupils
  • - tremors
  • - vomiting
  • - overheating
  • - seizures

What to do now

Contact ASPCA Poison Control (888-426-4435) or your vet immediately. Bring the packaging.

Data sources

Last reviewed: June 2026

Data error? Email data@treatortoxic.com with a source reference.

Also see: Dog toxin hub | Cat toxin hub | Emergency guide
Not veterinary advice. If your pet has ingested any potentially toxic substance, call ASPCA Poison Control 888-426-4435 or Pet Poison Helpline 855-764-7661 immediately. For emergencies, contact your veterinarian. This site is educational only.

Updated 2026-04-27