Dog Ate Chocolate? What to Do and When to Worry
Chocolate is one of the most common reasons owners call a pet poison line, especially around Halloween, Christmas and Easter. Whether it is an emergency depends on three things: the type of chocolate, how much was eaten and your dog's weight. Here is what to do, in order.
Do this right now
- Move your dog away from any remaining chocolate and keep the wrapper or packaging.
- Work out what was eaten: the type (milk, dark, baking chocolate or cocoa powder), roughly how much and when.
- Note your dog's weight, from the scales or the last vet visit.
- Call your vet or a poison line with those details. In the US: ASPCA Animal Poison Control Center (+1 888-426-4435) or Pet Poison Helpline (+1 855-764-7661). Elsewhere, call your vet or an out-of-hours clinic.
- Do not make your dog vomit at home unless a vet tells you to. Home methods such as salt can cause serious harm of their own.
Act quickly even if your dog seems fine. Signs usually begin 6 to 12 hours after eating, and treatment is simplest before then.
Why chocolate is toxic
Chocolate contains theobromine and caffeine, stimulants known as methylxanthines. Dogs break them down much more slowly than people do, so they build up and overstimulate the nervous system and heart. The fat in chocolate can also cause stomach upset and, in some dogs, pancreatitis one to three days later.
How much is in each type
Approximate methylxanthine content, from the Merck Veterinary Manual:
| Type | mg per gram | mg per ounce |
|---|---|---|
| Cocoa powder | 28.5 | 807 |
| Unsweetened baking chocolate | 15.5 | 440 |
| Cocoa bean hulls (garden mulch) | 9 | 255 |
| Semisweet and sweet dark chocolate | 5.3-5.6 | 150-160 |
| Milk chocolate | 2.3 | 64 |
| White chocolate | 0.04 | 1.1 |
The darker and more bitter the chocolate, the more dangerous it is. Bars with a very high cocoa percentage contain more than ordinary dark chocolate, so treat them as higher risk.
The doses vets work with
According to the Merck Veterinary Manual, in dogs:
- Around 20 mg per kg of body weight: mild signs such as vomiting, diarrhoea and increased thirst
- 40-50 mg/kg: effects on the heart, such as a racing or irregular heartbeat
- 60 mg/kg and above: seizures can occur
Individual dogs vary, so treat these as guides rather than guarantees. A vet or poison line can work out your dog's risk precisely, taking into account its health and anything else it may have eaten.
Worked examples
Multiply the grams eaten by the mg-per-gram figure, then divide by your dog's weight in kilograms (pounds divided by 2.2).
- A 10 kg (22 lb) dog eats a 45 g milk chocolate bar: 45 x 2.3 = about 104 mg, divided by 10 = about 10 mg/kg. This is below the level for mild signs, but still call your vet for advice; the fat and sugar alone can cause an upset stomach.
- The same dog eats 100 g of dark chocolate: 100 x 5.5 = 550 mg, divided by 10 = 55 mg/kg. That is in the range where heart effects are possible. Contact a vet now.
- A 5 kg (11 lb) dog licks out a bowl containing 10 g of cocoa powder: 10 x 28.5 = 285 mg, divided by 5 = 57 mg/kg. Also an emergency.
As the examples show, a small amount of baking chocolate or cocoa can be far more serious than a larger amount of milk chocolate, especially for small dogs. Do not forget the wrapper: foil and plastic can cause blockages too.
Symptoms to watch for
- Vomiting, diarrhoea, drinking and urinating more than usual
- Restlessness, panting or hyperactivity
- A racing heart, trembling or wobbliness
- Seizures or collapse, which are an emergency
Keep watching your dog closely for at least the next day, even if it seemed fine at first.
What the vet may do
Depending on the dose and how long ago it was eaten, a vet may safely make your dog vomit, give activated charcoal to reduce absorption, start intravenous fluids and use medicines to control the heart rate, tremors or seizures. Dogs that are treated early generally have the best outlook.
What about cats?
Cats are affected by the same compounds, but they rarely eat chocolate because they cannot taste sweetness. If your cat does eat some, call your vet in the same way.
Prevention
- Keep chocolate, baking cocoa and chocolate advent calendars in closed cupboards or high shelves. Dogs can smell chocolate through wrapping paper, so do not leave wrapped chocolate gifts under the tree.
- Ask children and guests not to share sweets.
- Check cakes, cereal bars and "human" treats for chocolate, raisins and xylitol.
- If you use cocoa bean shell mulch in the garden, consider a different mulch if your dog likes to chew things outside.
Related guides: Christmas foods that are toxic to dogs, dog ate grapes or raisins, Halloween pet safety and Thanksgiving pet safety.