What happens if my dog eats chocolate?

Chocolate contains theobromine, which dogs metabolise very slowly. Depending on the amount and type (dark chocolate is by far the worst), it can cause vomiting, diarrhoea, racing heart, tremors, seizures and even death. If your dog has eaten chocolate, ring your vet or an out-of-hours emergency line immediately.

Are grapes really toxic to dogs?

Yes. Grapes and raisins can cause acute kidney failure in dogs, even though the exact mechanism is still not fully understood. Toxicity is unpredictable — even tiny amounts can be dangerous. Always treat any quantity as an emergency.

What should I do if my dog has eaten something toxic?

Call your vet or a 24-hour emergency line straight away. Tell them what was eaten, the approximate amount and your dog’s weight. Do not try to make them sick without veterinary instruction — with some toxins it makes things worse.

Foods toxic to dogs: the complete list every owner should know

Why some human foods are dangerous for dogs

A dog’s metabolism handles certain compounds very differently from a human’s. Something harmless or even healthy for us can build up in a dog until it reaches toxic levels, or trigger severe reactions outright.

This list is essential reading for every owner. Do not wait for an accident before you learn it.

Highly toxic foods — immediate emergency

🍫 Chocolate and cocoa

Chocolate contains theobromine, an alkaloid dogs metabolise very slowly. Dark chocolate and cocoa powder are the most dangerous; white chocolate has less theobromine but is still harmful in large quantities.

Symptoms: vomiting, diarrhoea, excessive thirst, hyperactivity, muscle tremors, seizures, cardiac arrhythmia.
Dangerous dose: as little as 20 mg/kg of theobromine can cause serious symptoms.

🍇 Grapes and raisins

One of the most unpredictable toxins — the exact compound responsible is still debated. They can cause acute kidney failure even in small quantities. There is no established "safe dose".

Symptoms: vomiting (often within a few hours), lethargy, abdominal pain, reduced urination.

🧅 Onion, garlic and leek

All members of the Allium family. They contain sulphur compounds that damage red blood cells and cause haemolytic anaemia. Dangerous in every form: raw, cooked, powdered or dehydrated. Garlic is more concentrated than onion.

Symptoms: weakness, laboured breathing, brown or red urine, pale gums.

🪄 Xylitol (artificial sweetener)

Found in chewing gum, sugar-free sweets, "low-sugar" baked goods, some toothpastes and certain peanut butters. It triggers a massive insulin release that causes severe hypoglycaemia and can progress to liver failure.

Symptoms: vomiting, lethargy, loss of coordination, seizures (30–60 minutes after ingestion).

☕ Caffeine

Coffee, tea, energy drinks, caffeine tablets. Like theobromine, caffeine is a stimulant a dog’s body cannot handle well.

🥃 Alcohol

Even small amounts can cause vomiting, diarrhoea, breathing difficulties, metabolic acidosis and coma.

🌰 Macadamia nuts

The mechanism is unknown, but they cause a transient neurological syndrome: weakness in the hind legs, tremors, fever and low body temperature. Most dogs recover within 48 hours but need veterinary supervision.

Foods to avoid or give in strict moderation

🥑 Avocado

Contains persin, especially in the skin, stone and leaves. The flesh in small amounts rarely causes toxicity in dogs, but the stone is a choking and obstruction risk, and the skin and leaves are more dangerous. Best avoided.

🍖 Cooked bones

Cooked bones become brittle and can splinter. The fragments can perforate the oesophagus, stomach or intestine. Large raw bones are generally safer, but check with your vet before introducing them.

🍬 Sugar and sweets

Not directly toxic in small amounts, but they contribute to obesity, diabetes and dental disease. Watch out especially for artificial sweeteners (xylitol again).

🥛 Milk and dairy products

Many adult dogs are lactose intolerant. Dairy can cause diarrhoea and digestive upset, although it is not toxic in the strict sense.

🍟 Very salty or fatty foods

Excess salt can cause sodium toxicosis (vomiting, diarrhoea, tremors, seizures). Very fatty foods can trigger pancreatitis, particularly in predisposed breeds.

🍑 Stone fruits (cherry, peach, plum)

The stones contain cyanogenic glycosides that release cyanide when chewed. Small amounts of flesh are usually safe, but the stones are dangerous.

What to do if your dog has eaten something toxic

Stay calm and assess: what did they eat exactly? Roughly how much? When?
Call the vet immediately: do not wait for symptoms. With some toxins (xylitol, grapes) early intervention is dramatically more effective.
Do not induce vomiting without instruction: with caustics and oils it can make things worse.
Keep the packaging: bring the wrapper or note the ingredients so the vet can identify the toxin.

UK emergency contacts

Your own vet — most practices have an out-of-hours number that connects to a 24h emergency provider (Vets Now, MedivetNow).
Animal PoisonLine (UK, owner hotline run by the Veterinary Poisons Information Service): 01202 509000 (£35-45 per call, 24h).

Foods your dog CAN eat safely

It is not all about banning. Many human foods are safe and even beneficial: raw carrot, apple (no pips), plain cooked white rice, plain boiled chicken (no bones), courgette, watermelon (no rind or seeds), blueberries, plain cooked pumpkin.

The golden rule: if you are unsure, do not give it and ask your vet.

How CanAI helps

Log any suspected ingestion in CanAI’s health tracker so you have a timeline ready for the vet. Ask the AI chat about specific foods before sharing them. And if you do not have cover yet, compare options in dog insurance plans — poisoning emergencies can easily run to £1,500+.