My dog ate chocolate.
How bad is it?
Three answers and you'll know: your dog's weight, the chocolate type, roughly how much is gone. Thresholds from published veterinary toxicology.
If your dog is seizing or collapsed: call 855-764-7661 NOWHow this works
Chocolate's danger to dogs is theobromine (plus caffeine). Published veterinary thresholds: mild signs (vomiting, restlessness) start around 20 mg per kg of body weight, severe cardiac signs around 40 mg/kg, and seizures become possible around 60 mg/kg. Darker chocolate carries far more theobromine per ounce, baking chocolate is roughly 7x milk chocolate.
When in doubt, call
This calculator uses your estimates. Dogs also vary individually, and small dogs sit closer to every threshold. The hotlines are staffed 24/7 by veterinary toxicologists: Pet Poison Helpline 855-764-7661 (fee applies) or ASPCA Poison Control 888-426-4435.
What NOT to do
Do not induce vomiting unless a professional on the phone tells you to. Do not "wait and see" after dark or baking chocolate. Do not dose with hydrogen peroxide on your own.
When symptoms show up
Theobromine is absorbed slowly and cleared slowly, which is why a dog can look completely normal for hours and then get much worse. A rough timeline from published veterinary toxicology:
| Time since eaten | What is typical |
|---|---|
| 0 to 2 hours | Often nothing visible. This is the window where a vet can still decontaminate effectively. |
| 2 to 4 hours | Vomiting, diarrhoea, restlessness, obvious thirst, frequent urination. |
| 4 to 12 hours | Racing or irregular heartbeat, panting, tremors, agitation. This is the peak risk window. |
| 12 to 72 hours | Signs can persist. Theobromine has a long half-life in dogs, so a serious case is a multi-day problem, not a single bad evening. |
A normal-looking dog in the first hour is not reassurance. If the amount was large or the chocolate was dark, call before symptoms start, because the useful treatment window is early.
Theobromine by chocolate type
Type matters more than most people expect. The same 2 ounces is a shrug for a Labrador if it was milk chocolate and an emergency if it was baking chocolate.
| Type | Approx. theobromine | 2 oz for a 20 lb dog |
|---|---|---|
| White chocolate | ~0.01 mg/g | Effectively no theobromine risk |
| Milk chocolate | ~2 mg/g | Around 12 mg/kg, usually mild |
| Dark, 45 to 70% | ~5 mg/g | Around 31 mg/kg, call |
| Baking / 85%+ | ~16 mg/g | Around 100 mg/kg, emergency |
| Cocoa powder | ~26 mg/g | Around 163 mg/kg, emergency |
White chocolate is the one exception worth naming plainly: it contains almost no theobromine, so the usual worry does not apply. The fat and sugar can still cause vomiting or, in a prone dog, pancreatitis.
What the vet will actually do
Knowing this makes the call easier. Within roughly the first two hours the usual step is to induce vomiting in the clinic, followed by activated charcoal to bind what has already moved on. Charcoal is sometimes repeated, because theobromine is reabsorbed from the gut rather than passing straight through. From there it is supportive: IV fluids to push clearance, heart-rate monitoring, and medication for tremors or an abnormal rhythm if those appear. Most dogs seen early do well.
Common situations
It happened yesterday and the dog seems fine. Past about 72 hours with no signs at all, the risk has largely passed. Anywhere inside that window, describe the amount and type to a vet rather than deciding alone.
It was one M&M or a crumb. Run the numbers above. For most dogs over 20 lb a single small milk-chocolate item lands far below the 20 mg/kg mild-signs threshold. Small dogs sit much closer to every line.
Chocolate chip cookies or brownies. Estimate the chocolate alone, not the whole baked weight. Then consider what else was in it: raisins and xylitol are both more dangerous than the chocolate, and xylitol is a genuine emergency at any dose.
The wrapper is gone too. Mention it on the call. Foil and plastic can cause an obstruction, which is a separate problem from the theobromine.
You cannot tell how much is missing. Estimate high and call. Overestimating costs you a phone call; underestimating costs the treatment window.