Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Early signs of poisoning in dogs include vomiting, diarrhea, drooling, restlessness, trembling, wobbliness, unusual sleepiness, a racing heart, and seizures. But some of the most dangerous toxins, like rat poison, grapes, antifreeze, and xylitol, may cause no signs at first. If you think your dog ate something toxic, call your vet or a pet poison hotline right away rather than waiting for signs: ASPCA Animal Poison Control Center (888) 426-4435 or Pet Poison Helpline (855) 764-7661 (fees apply).
Early signs
- Vomiting or diarrhea
- Drooling or pawing at the mouth
- Restlessness, agitation, or pacing
- Trembling or twitching
- Wobbly walking
- Lethargy or unusual sleepiness
- Fast breathing or heart rate
- Pale, yellow, or brown gums
- Seizures or collapse
Toxins with delayed signs
- Anticoagulant rat poison: bleeding 3–5 days later
- Grapes and raisins: kidney failure over 1–3 days
- Antifreeze: early wobbliness, then kidney failure within a day or two
- Xylitol: low blood sugar within an hour or so, liver failure later
- NSAIDs: ulcers and kidney damage over days
What to do
- Remove your dog from the source
- Call your vet or a poison hotline
- Have the package, amount, and time ready
- Don’t induce vomiting unless instructed
Sources
- ASPCA Animal Poison Control Center: Top pet toxins
- Pet Poison Helpline: Poison list
- Merck Veterinary Manual: Toxicology overview in small animals
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.