If your dog has just eaten chocolate, please call your vet or the Animal PoisonLine (01202 509000) straight away, rather than reading on first. Have the packaging to hand if you can, as they will want to know exactly what was eaten and roughly how much. Do not wait to see if symptoms develop — with chocolate, getting ahead of the problem matters far more than reacting to it.
What makes chocolate dangerous
Chocolate contains theobromine, a stimulant from the same family as caffeine. Humans metabolise theobromine quickly and easily, but dogs break it down far more slowly, which means it builds up in their system and affects the heart, nervous system and digestive tract. Cats are also affected, though they are less likely to eat chocolate voluntarily since they cannot taste sweetness in the same way dogs can.
Not all chocolate carries the same risk. Cocoa powder and dark or baking chocolate contain by far the highest concentration of theobromine, followed by dark chocolate, then milk chocolate, with white chocolate containing barely any theobromine at all (though it is still not something to encourage, given its fat and sugar content, which can trigger pancreatitis in its own right).
Information your vet will want
Being able to answer a few key questions quickly will help your vet or the Animal PoisonLine assess the risk and advise you accurately, so try to gather this information while you are on the phone or before you call:
- What type of chocolate — dark, milk, white, cocoa powder, or baking chocolate?
- Roughly how much was eaten, and the packaging or brand if available.
- Your dog's approximate weight.
- When it was eaten, as closely as you can estimate.
- Whether your dog has shown any symptoms yet.
Timing and symptoms
Symptoms of theobromine poisoning typically start within a few hours of eating chocolate, though they can occasionally take up to twelve hours to appear, and can persist for a day or more because theobromine is broken down so slowly. Early signs include vomiting, diarrhoea, restlessness and excessive thirst. As it progresses, dogs can develop a rapid heart rate, tremors, high temperature and, in serious cases, seizures. This is exactly why prompt advice matters — treatment is far more effective when started before serious symptoms develop, often by making a dog sick under veterinary supervision within the first couple of hours.
What not to do
Please never try to make your dog sick at home, and never give any human medicine as a way of treating this. Home remedies for inducing vomiting are unreliable, can cause injury, and can waste crucial time. If your vet decides this is the right course of action, they have safe, effective veterinary-only methods and the ability to monitor your dog properly throughout. It is also worth remembering that everyday human painkillers such as paracetamol and ibuprofen are dangerous to dogs and cats and must never be given to try to ease any discomfort — always let your vet advise on pain relief.
An unexpected source: cocoa mulch
It is not just the biscuit tin to watch. Cocoa shell mulch, sold as a garden ground cover, is made from the discarded hulls of cocoa beans and can retain enough theobromine to pose a genuine risk to dogs who like to sniff around and eat things in the garden. It also tends to smell appealing to dogs, rather like actual chocolate, which makes it a particular hazard. If you have a dog who forages in the garden, it is worth choosing a different type of mulch or fencing off treated areas.
Prevention around Easter and Christmas
Chocolate poisoning cases spike predictably at Easter and Christmas, when chocolate is more plentiful, more visible, and often at dog height — think advent calendars on low shelves, selection boxes under the tree, or Easter egg hunts in the garden. A few simple habits go a long way at these times of year: keep chocolate on high shelves rather than coffee tables, brief visiting family and children (who may not know the risks or may want to share treats) about not feeding your dog anything from their pockets or bags, and check the garden for dropped or hidden eggs before letting your dog out unsupervised during an egg hunt. Our /my-pet-ate-something tool can help you quickly check other everyday foods and household items if you are ever unsure whether something your dog got into is a concern.
When to speak to your vet
To repeat the most important point in this guide: any chocolate ingestion in a dog is worth a call to your vet or the Animal PoisonLine (01202 509000) straight away, even if your dog seems completely fine so far. It is always better to make that call and be told there is nothing to worry about than to wait and watch symptoms develop. Estimates of risk based on chocolate type and quantity are only ever a guide — your vet's assessment of your individual dog always comes first.