My dog ate chocolate: what to do
Chocolate contains theobromine and caffeine, two stimulants that dogs metabolise far more slowly than people do. That is why an amount that does nothing to us can poison a dog. The purer the chocolate, the more theobromine it holds and the more dangerous it is.
Why chocolate is toxic to dogs
Theobromine and caffeine belong to a group called methylxanthines: they stimulate the heart and nervous system. A dog's body clears them very slowly (theobromine can take more than 17 hours to halve), so they build up and cause a racing heart, tremors and, in severe cases, seizures.
How much chocolate is dangerous?
It depends on two things: the type of chocolate (how much theobromine it contains) and the dog's weight. This table sums up the approximate theobromine content by type:
| Type of chocolate | Theobromine (per 100 g) | Risk |
|---|---|---|
| Pure cocoa powder | ~2,000 mg | Very high |
| Dark / baking chocolate | ~500–1,600 mg | High |
| Milk chocolate | ~150–220 mg | Medium |
| White chocolate | almost 0 mg | Low (but fat and sugar) |
As a rough guide, the first symptoms tend to appear from around 20 mg of theobromine per kilo of the dog's body weight, and severe cases above 40–60 mg/kg. Translated into dark chocolate:
| Dog's weight | Risk starts from |
|---|---|
| 5 kg | around ~15–20 g |
| 10 kg | around ~30–40 g |
| 20 kg | around ~60–80 g |
| 30 kg | around ~90–120 g |
Symptoms and how soon they appear
Signs usually begin between 2 and 12 hours after eating the chocolate and can last several days. A rough guide:
- First hours: restlessness, nervousness, lots of thirst and urination, vomiting or diarrhoea.
- Following hours: panting, tremors, fast heartbeat, hyperactivity.
- Severe cases: arrhythmias, muscle stiffness, seizures. These need immediate veterinary care.
What to do step by step
- Find out what and how much it ate: type of chocolate, rough amount and what time.
- Keep the wrapper to show the vet the composition.
- Call an emergency vet with that information. This is the most important step and shapes the rest.
- Follow their instructions. If they tell you to come in, go as soon as possible; sometimes vomiting is induced at the clinic when the intake is recent.
- Watch your dog on the way and note any new symptom.
What NOT to do
- Don't "wait and see": the sooner you act, the wider your margin.
- Don't induce vomiting on your own without professional advice; doing it wrong can make things worse.
- Don't give milk, coffee or home remedies.
- Don't feed more food thinking it will "dilute" the chocolate.
What the vet will do
Treatment depends on how much time has passed and the amount. It may include:
- Inducing vomiting when the intake is recent (usually within the first 1–2 hours).
- Activated charcoal to reduce theobromine absorption.
- Fluid therapy (intravenous fluids) to help clear it and stabilise the animal.
- Medication and cardiac monitoring if there is a fast heart rate, tremors or seizures.
With prompt treatment, most dogs recover fully.
What if it is a cat that eats chocolate?
Cats are even more sensitive to theobromine, although they rarely eat sweets because they can't taste them. If your cat has tried chocolate, follow the same steps: identify the type and amount and call the vet.
How to stop it happening again
- Keep chocolate and baking cocoa in closed cupboards, out of reach.
- Take extra care at Christmas and Easter, when there are more sweets around.
- Tell children and visitors not to give the dog chocolate.
- Keep the phone number of your nearest emergency vet handy.
Frequently asked questions
How much chocolate can kill a dog?
There is no single figure: it depends on the type of chocolate and the dog's weight. Severe cases appear above around 40–60 mg of theobromine per kilo, which in dark chocolate can be a relatively small amount for a small dog. That is why, with any intake, the safe move is to call the vet.
What if it only licked a bit or ate one square?
A small amount of milk chocolate in a large dog is usually just a scare, but one square of dark chocolate in a small dog can already be worth a consultation. Work out the dog's weight and the type of chocolate and, if in doubt, call.
Are puppies and small dogs at greater risk?
Yes. The lower the weight, the less theobromine needed to cause poisoning. With puppies and small breeds, take extra care and consult as soon as possible.
Is white chocolate dangerous too?
White chocolate has almost no theobromine, so the poisoning risk is low, but its high fat and sugar content can cause vomiting, diarrhoea or even pancreatitis. If there are symptoms, consult a vet.
How long does it take to have an effect?
Symptoms usually appear 2 to 12 hours after ingestion and can last several days. That is why you should act immediately and not wait for them.
Should I make it vomit?
Not on your own. Inducing vomiting incorrectly can be dangerous. Call a vet first, who will tell you whether and how to do it.
Is cocoa or baking chocolate more dangerous?
Yes. Pure cocoa powder and dark baking chocolate concentrate far more theobromine than milk chocolate, so the same amount is considerably more dangerous.
This is first-aid guidance only and does not replace a vet's diagnosis. In any emergency, contact a professional.
