Do this right now
- Phone your vet. If they're closed, phone the out-of-hours vet. Their answerphone or website will tell you who covers your area. Don't wait for the morning, and don't wait for symptoms.
- Have these ready: your dog's weight, what kind of chocolate it was, roughly how much, and what time they ate it. Keep the wrapper; it helps the vet work out how much of the poison was in it.
- Don't make your dog sick yourself. Salt water and other home remedies can be dangerous. The vet can do it safely, usually within the first hour or two.
- Move the rest of it out of reach, and check whether any other pets got some too.
If you think your pet has eaten something poisonous, the Animal PoisonLine can also help (there is a charge). Your vet comes first.
How much did they eat?
Pick what your dog ate and how much. The checker uses the strength of that chocolate and your dog's weight to give you a rough number to tell the vet. It never tells you to wait. Whatever it shows, phone a vet.
How it works: theobromine and caffeine (the poisons in chocolate) per gram for each type, times the amount, divided by your dog's weight. It rounds towards caution: we use the strongest typical figures, and dark chocolate is worked out from its cocoa %. Signs can start from about 20 mg per kg of body weight, heart problems from 40–50, and fits from about 60 [2]. Brands vary, and some dogs are more sensitive, so only a vet can say what's right for your dog.
Why chocolate is dangerous
Chocolate contains theobromine, and a little caffeine, both stimulants. People break them down quickly; dogs don't. Theobromine reaches its highest level in a dog's blood about 10 hours after eating [2], and it over-stimulates the heart and nervous system. How dangerous it is depends on the type of chocolate, how much was eaten, and the size of the dog.
Which chocolate is strongest?
The darker the chocolate, the more poison it has. Here's roughly how much is in each gram [3]:
| Type | Poison per gram (theobromine + caffeine) |
|---|---|
| Cocoa powder (baking, not drinking chocolate) | about 28 mg |
| Unsweetened cooking chocolate (100% cocoa) | about 16 mg |
| Dark chocolate, 70% (e.g. a dark 100 g bar) | about 11 mg |
| Plain chocolate, 36–45% (Bournville 36%, dark Chocolate Orange 43%) | about 6–7 mg |
| Drinking chocolate powder | about 8 mg |
| Milk chocolate (Dairy Milk 20%, Galaxy 25%, most selection boxes) | about 2.3 mg |
| Richer milk chocolate (Toblerone 28%, Lindor 32%) | about 2.6–3 mg |
| White chocolate | almost none, but very fatty |
Percentages are the "cocoa solids" minimum on UK labels. Dark and richer milk chocolate figures are our estimate from the cocoa %, based on the published figures for 100% cooking chocolate and for milk chocolate; they round up on purpose. Drinking chocolate assumes about 28% cocoa.
Raisins are a second danger. Fruit and nut chocolate, Christmas pudding, mince pies, Christmas cake and rum and raisin can cause kidney failure in dogs, and there's no known safe amount. Liqueur chocolates add alcohol. If any of these were eaten, phone a vet now whatever the amount.
Real UK chocolate, by weight
Pack sizes change (and keep shrinking), so check the wrapper if you have it. These are typical UK sizes in October 2026:
| What | About | Type |
|---|---|---|
| Cadbury Dairy Milk, standard bar | 45 g | Milk (20%) |
| Cadbury Dairy Milk, big bar | 180 g | Milk (20%) |
| Galaxy, standard bar | 42 g | Milk (25%) |
| KitKat, 4 finger | 41.5 g | Milk (part wafer) |
| Maltesers, bag | 37 g | Milk (25%) |
| Toblerone, 100 g bar | 100 g | Milk (28%) |
| Advent calendar, one door (Dairy Milk calendar, 90 g) | 3.75 g | Milk (20%) |
| Chocolate coin, one | 5–6 g | Milk |
| Quality Street, Celebrations or Heroes, one sweet | 8–9 g | Mostly milk |
| Quality Street tub | 550 g | Mostly milk |
| Lindor truffle or Ferrero Rocher, one | 12.5 g | Milk (Lindor 32%) |
| Terry's Chocolate Orange, whole (20 segments) | 145 g | Milk (25%), or dark (43%) |
| Cadbury Bournville | 100 g or 180 g | Plain (36%) |
| Selection box, whole | 100–250 g | Milk |
| Hollow chocolate Santa or Easter egg (medium) | about 100 g | Usually milk |
| Green & Black's dark (70% or 85%) | 90 g | Dark |
| Lindt Excellence dark (70%, 85%, 90%) | 100 g | Dark |
| Dr. Oetker Extra Dark cooking chocolate | 100 g | Dark (72%) |
| Cocoa powder, 1 tablespoon | about 6 g | Cocoa |
| Hot chocolate, one mug of powder | about 20–25 g | Drinking chocolate |
| Chocolate brownie, one square | about 60 g | Varies (homemade is often strong) |
All of these are in the checker. Brand names are given only to help you work out what was eaten.
What it means for your size of dog
Roughly how much it takes to reach the level where signs can start (20 mg per kg). Less than this still needs a phone call: some dogs are more sensitive, and the vet may still want to see them.
Chihuahua, Yorkie, toy poodle
- one standard Dairy Milk bar (45 g)
- or one square of a 100 g bar of 70% dark (9 g)
- or a heaped half tablespoon of cocoa powder
Jack Russell, Shih Tzu, Dachshund
- about 8 segments of a milk Chocolate Orange
- or 16 advent calendar doors
- or 1¼ squares of a 100 g bar of 70% dark (13 g)
Cocker Spaniel, Springer, Staffie
- about 3 standard Dairy Milk bars (130 g)
- or 15 Quality Street or Celebrations
- or 2½–3 squares of a 100 g bar of 70% dark (27 g)
Labrador, Golden Retriever, German Shepherd
- a big 180 g Dairy Milk bar and almost half another (260 g)
- or half a 100 g bar of 70% dark (54 g)
- or 3½ tablespoons of cocoa powder
Pictures are drawn to scale with the numbers: the dark part is the amount, the pale part is the rest of the pack. A "square" here is one tenth of a 100 g bar; squares vary by brand, so go by the bar's weight.
Worked out with milk chocolate at 2.3 mg per gram and 70% dark at about 11 mg per gram. Double these amounts and you're near the level where the heart can be affected.
The first hours: what happens when
The best time to phone. A vet can often make your dog sick and bring the chocolate back up. In a UK study, a quarter of dogs reached the vet within an hour [1].
Signs usually start, most often within 2–4 hours: being sick, thirst, restlessness [2]. The vet can still help with charcoal and fluids.
The poison peaks around 10 hours and leaves the body slowly. Serious signs (racing heart, shaking, fits) can last a day or more.
What to say on the phone
"My dog [name] has eaten chocolate. She's a [breed], about [weight] kg. She ate about [amount] of [type, e.g. a Dairy Milk bar, or 70% dark], around [time]. She seems [fine / sick / restless]."
Have these to hand:
- your dog's weight (a guess is fine)
- the wrapper, or a photo of it: the cocoa % and weight are on it
- roughly how much is missing, and the time
- anything else they might have eaten: raisins, nuts, sugar-free sweets or gum (xylitol), wrappers or foil
- any health problems or medicines, especially heart problems or fits
Then do what the vet says. If they want to see your dog, go straight away, and take the wrapper.
Signs of chocolate poisoning
Signs usually start within 2 to 12 hours, and can last a day or more:
- being sick or diarrhoea
- drinking a lot, and needing to wee more (or accidents indoors)
- restlessness, over-excitement, or not settling
- panting, or a racing heart
- wobbling, twitching or shaking
- fits (seizures) or collapse, in serious cases
If you see any of these, go to a vet straight away. But don't wait for them before phoning.
What the vet might do
- If your dog ate it recently, the vet can give an injection to make them sick and bring the chocolate back up.
- They may give activated charcoal, which soaks up what's left in the gut.
- Dogs with symptoms may need a drip, heart monitoring and medicine to calm them, sometimes overnight.
- Most dogs treated early recover well. In the UK study of 375 dogs seen by vets for chocolate, none had life-threatening signs [1].
Christmas, Easter and Halloween
A University of Liverpool study of UK vet records found dogs were nearly 5 times more likely to see a vet for chocolate at Christmas, and twice as likely at Easter, than the rest of the year [1]. The chocolate involved included gift boxes and selection boxes, Easter eggs, chocolate cake, Chocolate Oranges, Toblerone, liqueurs, chocolate Santas, advent calendars and tree decorations.
Christmas
- Advent calendars: hang them up high. A dog can eat a whole calendar, tray and all, in seconds.
- Never put chocolate decorations on the tree, or wrapped chocolate presents under it. Dogs can smell through wrapping paper.
- Selection boxes and tubs: keep them in a cupboard, not on the coffee table.
- Christmas pudding, mince pies and Christmas cake contain raisins, which are dangerous too.
- Ask visitors to keep their bags shut and off the floor.
Easter and Halloween
- Easter egg hunts: count the eggs out and count them back in. Dogs find the ones children miss.
- Keep the trick-or-treat bowl up high, not by the door.
- Children's sweet bags left on the floor are an easy target.
- Sugar-free sweets and gum can contain xylitol, which is very dangerous for dogs.
- Wrappers and lolly sticks can cause a blockage if swallowed.
Myths
"My dog ate chocolate before and was fine."
Last time may have been a little milk chocolate. A bigger amount, darker chocolate, or a smaller dog changes everything. Phone each time.
"White chocolate is safe."
It has almost no theobromine, but it's very fatty and can cause a bad stomach upset or pancreatitis (a painful, inflamed pancreas). Still phone a vet.
"Give salt water to make them sick."
Salt water can cause salt poisoning, which can be more dangerous than the chocolate. Only a vet should make your dog sick.
"Dog chocolate is real chocolate, so a bit of mine is fine."
Chocolate treats made for dogs are made without theobromine, often using carob. Human chocolate isn't the same.
"Wait and see if they get ill."
By the time signs show, it's too late to bring the chocolate back up. The first hour or two is when the vet can do the most.
Cats, rabbits and other pets
Chocolate is poisonous to cats, rabbits, guinea pigs and other pets too. Cats rarely eat it, but if yours or another pet has, phone a vet in the same way. The checker above is for dogs only.
Questions owners ask
Is it OK if my dog accidentally eats chocolate?
Phone a vet now, even if it was only a little and your dog seems fine. Whether it's dangerous depends on the type of chocolate, how much, and your dog's weight. A vet can work that out in a couple of minutes, and treatment works best in the first hour or two.
How long after eating chocolate will a dog get sick?
Signs usually start 2 to 12 hours after eating chocolate, most often within 2 to 4 hours, and can last a day or more, occasionally up to 3 days. Don't wait for signs before phoning a vet.
My dog got into chocolate. What do I do?
Move the rest out of reach, keep the wrapper, note the time, and phone your vet or the out-of-hours vet now. Tell them your dog's weight, the type of chocolate and roughly how much is missing. Don't try to make your dog sick at home.
My dog ate chocolate but seems fine. Do I need to do anything?
Yes, phone a vet now. Signs often take several hours to appear, and treatment works best before then. Your vet can tell you from your dog's weight and what they ate whether it's a dangerous amount.
Which chocolate is most dangerous for dogs?
Cocoa powder is the strongest, then cooking chocolate and dark chocolate (the higher the cocoa percentage, the more dangerous). Milk chocolate is weaker but can still poison a dog, especially a small one. White chocolate has very little of the poison but is very fatty and can upset the stomach or pancreas.
Should I make my dog sick after eating chocolate?
No. Never try to make your dog sick at home. Salt water can cause salt poisoning, and other home remedies can be dangerous too. A vet can give an injection that makes your dog sick safely, usually within the first hour or two.
My dog ate the wrapper too. Is that a problem?
Tell the vet. Foil and plastic wrappers, advent calendar trays and lolly sticks can cause a blockage, especially in a small dog. Watch for repeated sickness, a sore tummy or not pooing.
Are chocolate treats for dogs safe?
Chocolate-flavoured treats made for dogs are made without the harmful ingredient (often using carob), so they're fine in normal amounts. Human chocolate isn't.
A Christmas card from Max
"Dear humans, I love you, and I love the smell of your advent calendar. Please hang it up high, so I don't keep dreaming about how I'll get to it. Love, Max x"
Send this guide to a dog owner you know before the selection boxes come out.
Sources
- Noble, Newman, Wyatt, Radford and Jones (2017). Heightened risk of canine chocolate exposure at Christmas and Easter. Veterinary Record. University of Liverpool, using records from 229 UK vet practices (SAVSNET).
- Cortinovis and Caloni (2016). Household food items toxic to dogs and cats. Frontiers in Veterinary Science. Source of the 20, 40–50 and 60 mg per kg levels, and the timings.
- Kovalkovičová and others (2009). Some food toxic for pets. Interdisciplinary Toxicology. Includes the methylxanthine table from the Merck Veterinary Manual.
- Pack weights: manufacturers' and UK supermarket listings, checked October 2026.
This guide is general advice for UK pet owners. It doesn't replace your vet, who knows your pet, and the checker is a rough guide only: it can't tell you a dog is safe. If your pet has eaten something poisonous, always phone a vet straight away.