Chocolate Poisoning in Dogs

Chocolate contains theobromine and caffeine, both methylxanthines. Dogs break these down much more slowly than people, so theobromine builds up. The darker and more concentrated the chocolate, the more theobromine it contains.

This page is the clinical guide. If you only needed a yes/no, start at can dogs eat chocolate? — the answer is no — then come back here for dose bands and what vets do.

UK veterinary poison guidance commonly uses approximate theobromine dose bands (always confirm with your vet — individual sensitivity varies):

UK seasonal traps: Easter eggs, advent calendars, selection boxes, baking cupboards, and guests’ handbags. Cocoa mulch in gardens is a separate theobromine source — keep dogs off it.

Use our chocolate toxicity calculator for a rough estimate, then phone your vet regardless of the result. A “low” band is not permission to wait.

Signs usually appear within 2–12 hours and may include:

• Vomiting and diarrhoea
• Restlessness or hyperactivity
• Increased thirst and urination
• Rapid heart rate or panting
• Muscle tremors or twitching
• Seizures (severe cases)
• Collapse

Severe poisoning can cause heart arrhythmias and, without treatment, can be fatal — especially in small dogs or after dark or baking chocolate.

1. Call your vet or Animal PoisonLine (01202 509000) now — do not wait for symptoms.
2. Tell them the type, approximate amount, time eaten, and weight.
3. Do not induce vomiting unless a vet instructs you to.
4. Keep the wrapper — cocoa percentage helps.
5. Mention any xylitol (“sugar-free”) products in the same raid. That is a second poison — see xylitol poisoning.

If advised to go in, treatment may include induced vomiting if recent, activated charcoal, IV fluids, heart monitoring and anti-seizure medication. Out of hours use the out-of-hours directory.

Recent ingestion in a stable dog may be decontamination first. Later presentations focus on heart rhythm, temperature, blood pressure and stopping tremors. Caffeine in chocolate adds to the stimulant load; baking chocolate and cocoa powder pack more theobromine per gram than a milk Easter egg of the same weight.

Small dogs and puppies reach toxic mg/kg faster. A “family bar” shared on the floor is not one dose — it is however many grams that animal ate. If two dogs raided the same tin, both need advice.

Do not give human heart tablets, salt, or milk as home treatment. The calculator plus the wrapper is what the phone call needs. If the amount is unknown — shredded wrapper, multiple dogs, or chocolate in a mixed dessert — say so. Unknown is still a reason to go in, not a reason to wait.

Keep all chocolate out of reach, including baking ingredients. Remind children and guests. If the dog is a known counter-surfer, shut the kitchen. Grapes and raisins are a different, no-safe-dose emergency — grape poisoning. After any confirmed chocolate ingestion, even if the clinic sends you home, watch overnight for restlessness, panting or vomiting and go back if those start. Do not give leftover anti-sickness tablets from a previous illness unless the vet says so tonight. Water is fine in small sips if they can swallow.