My dog ate chocolate: how much is too much?
Call your vet or an animal poison control line now
Do not wait for symptoms. Signs of chocolate poisoning usually start 6–12 hours after eating, and calling early gives your vet the most options.
Both are US lines and may charge a consultation fee. Outside the US, call your own vet or the nearest emergency vet clinic. Do not give any home treatment unless a vet tells you to.
Mild signs possible (from 20 mg/kg)
Merck lists vomiting, diarrhoea and drinking more than usual from about this dose.
Whatever the number, call now: only a vet who knows your dog can decide what to do, and acting early gives the most options.
How the dose is worked out
Chocolate contains theobromine and some caffeine, stimulants known together as methylxanthines. The calculator multiplies the amount eaten by the methylxanthine content the Merck Veterinary Manual gives for that kind of chocolate, then divides by your dog's weight. Per gram, Merck lists about 28.5 mg in cocoa powder, 15.5 mg in unsweetened baking chocolate, 9 mg in cocoa bean mulch, 5.3–5.6 mg in semisweet and sweet dark chocolate, 2.3 mg in milk chocolate and 0.04 mg in white chocolate. The darker and less sweet the chocolate, the more dangerous it is.
The dose is then compared with the levels at which Merck reports effects in dogs: mild signs such as vomiting, diarrhoea and thirst from 20 mg/kg, effects on the heart from 40–50 mg/kg and seizures from 60 mg/kg. In severe cases signs can last up to 72 hours. Merck also notes that the fat in chocolate can trigger pancreatitis in some dogs.
Sources
- Merck Veterinary Manual, Chocolate Toxicosis in Animals (methylxanthine content by product, dose effects, timing of signs).
- ASPCA, People Foods to Avoid Feeding Your Pets; ASPCA Animal Poison Control Center; Pet Poison Helpline.
Questions
My dog seems fine. Do I still need to call?
Yes. Merck says signs usually appear 6–12 hours after eating, so a dog can look perfectly well at first. A quick call lets a vet or poison line weigh up your dog's size, health and what was eaten, and tell you whether anything needs doing.
The dose is below 20 mg/kg. Is my dog safe?
Probably less at risk, but not certainly safe. Chocolate varies, the amount eaten is often a guess and some dogs react more than others. Call anyway and let a professional decide.
Is white chocolate dangerous?
Merck calls white chocolate a negligible source of methylxanthines, so poisoning from it is unlikely. Its fat can still trigger pancreatitis in some dogs, so call your vet if your dog ate a lot of it.