The single most important idea on this page: several of these poisons have a delay built in. Grapes can take a day before anything shows. Onion damage typically appears three to five days later. "He seems fine" is not reassurance — it is often just the early part of the timeline.
Call after a suspected ingestion, not after symptoms.
How we label our evidence
- Source-supportedStated directly in the cited institutional publication.
- Our editorial guidanceA conservative reading of the evidence applied to a caregiver decision. Not a validated clinical protocol.
- Evidence gapWe could not verify this in our approved sources, so we have not invented a number.
Keep out of reach
| Food | What it does and when | Action |
|---|---|---|
| Grapes, raisins, sultanas, currants | Acute kidney injury. The toxic dose is unpredictable — tartaric acid content and individual susceptibility both vary. Vomiting or diarrhoea may start 6–24 hours later, kidney signs over 1–3 days. | Call now after any amount, even if the dog seems well. There is no verified safe grape count. |
| Chocolate and cocoa | Theobromine and caffeine hit the gut, heart and nervous system: vomiting, marked restlessness, fast heartbeat, tremors, seizures. Concentration matters enormously. | Call now with the exact product and amount. Seizures or collapse — emergency. |
| Xylitol | In sugar-free gum, sweets, some peanut butters, medicines and toothpaste. Dangerous low blood sugar, and liver injury can also occur. Weakness, confusion, vomiting, tremors or seizures can begin within 30–60 minutes. | Call immediately and bring the packaging. Do not wait for weakness. |
| Onion, garlic, chives, leeks | Raw, cooked and powdered all damage red blood cells. Haemolysis commonly develops 3–5 days after exposure: weakness, pale gums, jaundice, dark urine, fast breathing, collapse. | Call now for a dose assessment — especially powders. Cooking does not remove the hazard. |
| Macadamia nuts | Weakness, incoordination, vomiting, tremors and overheating, usually within 12 hours. Generally self-limiting, often resolving in 12–48 hours. | Call now — and note that chocolate-coated versions stack two hazards. Severe weakness or neurological signs are an emergency. |
| Alcohol | Rapidly absorbed. Vomiting, incoordination, low body temperature, depressed consciousness, seizures, respiratory failure. | Call now. No "safe sip" allowance is established. |
| Raw yeast dough | Expands in the stomach and produces ethanol — distension and alcohol poisoning can happen together. | Call now. A swollen abdomen with unsuccessful retching or distress is an emergency. |
| Bones, cooked or raw | Tooth fracture and gastrointestinal injury. | Call after swallowing. Choking or severe pain is an emergency. |
| Rich fatty scraps | Digestive illness, and may trigger pancreatitis. | Get prompt advice for vomiting or abdominal pain rather than assuming it was "just a rich meal." |
Chocolate numbers — context, not a home clearance test
Source-supported
Merck lists approximate combined methylxanthine concentrations of 28.5 mg/g for cocoa powder, 15.5 mg/g for unsweetened baking chocolate, 5.3–5.6 mg/g for dark and semisweet, and 2.3 mg/g for milk chocolate. Mild signs are described around 20 mg/kg of body weight, cardiac effects at 40–50 mg/kg, and seizures at 60 mg/kg or above.
Our editorial guidance
Those units are methylxanthines, not grams of chocolate — and product composition and individual sensitivity vary. They exist to explain why a piece of baking chocolate is a different problem from a piece of milk chocolate, not to let you calculate your way out of calling. We have deliberately not built a chocolate calculator.
What you can safely give
Cornell suggests carrots, broccoli and snap peas as lower-calorie options — or simply using part of the normal daily ration as treats. WSAVA also lists lean cooked meats. Serve small, plain and boneless; wash vegetables, skip sauces and seasoning, and supervise.
Human-food snacks never replace a complete balanced diet, and chicken and rice is not a nutritionally complete long-term menu.
Our editorial guidance
The arithmetic. All extras together should stay under 10% of daily calories. At 500 kcal/day that is under 50 kcal/day — dental chews and training rewards included. It comes out of the daily allowance, not on top of it. See the 10% rule.
A prescription diet can rule these choices out entirely, and during a diagnostic elimination diet the controls are stricter still — see itching and food allergy.
When to act
What the action labels mean
- Emergency now —
- contact an emergency veterinary service and arrange immediate assessment. Do not wait for the next scheduled feed or weigh-in.
- Call now for triage —
- telephone the veterinary service when you notice the sign. The veterinarian decides how quickly the animal needs to be seen.
- Contact today —
- get in touch when you notice the issue to agree on a time. This does not mean waiting until evening.
Emergency now
Choking or breathing difficulty; collapse, seizure or severe incoordination; a painful distended abdomen with repeated unsuccessful retching; marked weakness with pale gums; or inability to urinate after a concerning ingestion. Arrange transport while you call.
Call now for triage
Any suspected grape, raisin or xylitol ingestion, and suspected exposure to anything else in the table. Have ready: the dog's weight in kg, the product and ingredient list, the estimated amount or item count, the time, any symptoms, and the packaging. If you don't know the quantity, say so — the clinic decides what happens next.
Contact today
Recurrent digestive upset after otherwise acceptable treats, trouble staying inside the calorie allowance, or uncertainty about extras alongside kidney disease, pancreatitis, obesity or a prescribed diet. This tier is for feeding questions, not suspected poisoning.
Emergency now
At home: remove access and keep the package. That is the whole list. Do not induce vomiting, and do not give salt, oil, milk, charcoal or human medication unless a veterinarian gives you case-specific instructions. A home remedy can delay or complicate the real treatment.
Two myths
- "A small amount is always safe." For grapes in particular there is no established safe dose, and susceptibility differs between dogs.
- "If he looks normal we can wait and see." Onion and grape toxicity are specifically delayed. Absence of signs does not exclude poisoning.
Evidence gap
No reliable universal safe grape dose, no human-food portion table that fits every dog, and no home chocolate-clearance threshold were verified in our sources. Uncertainty about an individual toxic dose does not make the hazard speculative — it makes the phone call the right first move.
Sources
- Cornell Riney Canine Health Center Grape and raisin toxicity
- Cornell Riney Canine Health Center Xylitol toxicities
- Merck Veterinary Manual Chocolate Toxicosis in Animals (February 2026)
- Merck Veterinary Manual Garlic and Onion (Allium spp.) Toxicosis in Animals (September 2024)
- Merck Veterinary Manual Macadamia Nut Toxicosis in Dogs (September 2024)
- Merck Veterinary Manual Toxicoses From Alcohols in Animals (March 2025)
- Merck Veterinary Manual Bread Dough Toxicosis in Animals (August 2025)
- WSAVA Feeding Treats to Your Dog (PDF)
- Cornell Riney Canine Health Center Re-evaluating Your Dog's Diet
- Cornell Riney Canine Health Center Holiday Hazards (December 2025)