Chocolate Toxicity in Dogs: At a Glance
Chocolate toxicity is dose-dependent. Dark chocolate and baking chocolate are the most dangerous.
Theobromine Content by Chocolate Type (mg/oz)
Chocolate Type
| Chocolate Type | Theobromine/oz | Toxic for 20lb Dog | Toxic for 50lb Dog | Symptoms Onset |
|---|---|---|---|---|
| White Chocolate | ~1 mg | >200 oz (not realistic) | >500 oz (not realistic) | N/A — negligible risk |
| Milk Chocolate | ~60 mg | ~3-5 oz | ~8-12 oz | 2-12 hours |
| Dark Chocolate (60%) | ~180 mg | ~1-2 oz | ~3-5 oz | 2-12 hours |
| Baking Chocolate | ~450 mg | ~0.5-1 oz | ~1-2 oz | 1-4 hours |
| Cocoa Powder | ~800 mg | ~0.25-0.5 oz | ~0.5-1 oz | 1-4 hours |
Chocolate Ingestion: What to Do
| Identify chocolate type and amount eaten — check the wrapper | |
| Call your vet or Pet Poison Helpline (855-764-7661) immediately | |
| Do NOT induce vomiting unless instructed by a vet | |
| Watch for symptoms: vomiting, diarrhea, restlessness, rapid heart rate, tremors, seizures | |
| Bring chocolate wrapper to vet — helps calculate theobromine dose | |
| Wait and see if symptoms develop — chocolate toxicity is time-sensitive | |
| Induce vomiting with hydrogen peroxide without vet instruction | |
| Assume 'it was just a little bit' — dark chocolate is potent |
The toxic dose of theobromine is ~100-200 mg per kg of dog body weight. A 20lb (9kg) dog needs only ~900-1800mg of theobromine for severe toxicity. That's just 2-4 oz of dark chocolate or 0.5-1 oz of baking chocolate. Small amounts of dark chocolate can be lethal.
Symptoms can take 2-12 hours to appear, but theobromine stays in a dog's system for 17+ hours (vs 6-8 hours in humans). Dogs can't metabolize it efficiently. Even if your dog seems fine after 2 hours, they can still develop severe symptoms. Seek veterinary care immediately.
The toxic dose depends on both the type of chocolate and your dog's weight: baking and dark chocolate contain roughly 6 to 10 times more of the toxic compound theobromine than milk chocolate, so a small dog eating even an ounce of dark chocolate can reach a dangerous dose. Signs often take 6 to 12 hours to show up, so a dog that seems fine right after eating it isn't necessarily out of the woods.
Not all chocolate is the same risk
Type and your dog's weight decide how dangerous this is.
petstore.comSigns to watch for in the next 12-72 hours
Chocolate's danger comes from a compound dogs can't clear like we do
Theobromine, the compound that makes chocolate toxic to dogs, breaks down much slower in a dog's body than in a human's, so it builds up in their system instead of clearing out. Caffeine adds a smaller effect on top of that.
The darker and more bitter the chocolate, the more theobromine per ounce: baking chocolate and unsweetened cocoa carry the most, milk chocolate far less, and white chocolate has barely a trace.
The same amount of chocolate is not the same risk for every dog
A dose of roughly 20 mg of theobromine per kilogram of body weight causes mild signs like vomiting and restlessness; 40 to 50 mg/kg starts affecting the heart; and above 60 mg/kg risks tremors and seizures.
That means a 10-pound dog and a 70-pound dog eating the exact same candy bar are not facing the same risk at all - the smaller dog crosses those thresholds with far less chocolate. "How much did they eat" always has to be paired with "how much do they weigh."
Signs show up slowly and then stick around
Chocolate poisoning doesn't show up in minutes; signs typically start 6 to 12 hours after eating it, beginning with vomiting, diarrhea, and restlessness. Because theobromine takes so long to clear a dog's system, a serious case can drag on for up to 72 hours, not just one bad afternoon.
A dog that seems fine 2 hours after eating chocolate is not necessarily out of the woods yet.
The ASPCA identifies baking chocolate and unsweetened cocoa as carrying substantially more theobromine per ounce than milk chocolate, with white chocolate containing only trace amounts, and lists vomiting, diarrhea, restlessness, an elevated heart rate, tremors, and seizures as the escalating signs of ingestion. The Merck Veterinary Manual describes theobromine toxicosis in dogs as dose-dependent, with mild gastrointestinal signs at lower doses, cardiac effects at moderate doses, and central nervous system signs including tremors and seizures at higher doses, and notes that clinical signs commonly begin several hours after ingestion and can persist for more than a day given theobromine's slow clearance in dogs.
Use the Toxicity Checker to enter the chocolate type and your dog's weight and see roughly where the dose falls on this scale.