Reference data
Toxic doses quick reference for dogs and cats
The toxic doses this site publishes for dogs and cats: chocolate bands, allium range, grape and raisin references, and emergency numbers.
Every dose below is quoted exactly as the site's dog and cat toxicity calculators state it, in the units those pages use. This table is a reading aid for someone who already has a number in front of them; it does not work out a dose for you.
Run the arithmetic on the calculator for your animal's weight, then use this table to see where the result sits. A figure below a threshold is not a clearance, and a figure at or above one is a reason to be on the phone straight away.
| Substance or exposure | Species | Dose as published on this site | Note |
|---|---|---|---|
| Chocolate (methylxanthines) | Dog | About 20 mg/kg: mild signs | Vomiting, diarrhoea and restlessness typically begin 6–12 hours after ingestion |
| Chocolate (methylxanthines) | Dog | 40–50 mg/kg: cardiotoxic range | Heart-rhythm disturbances are likely; contact a veterinarian now |
| Chocolate (methylxanthines) | Dog | 60 mg/kg and above: seizure risk | Seizures are expected at this dose; get to a clinic immediately |
| Chocolate (methylxanthines) | Dog | LD50 100–200 mg/kg: potentially lethal | Seizures, collapse and fatal heart rhythms are reported in this range |
| Chocolate (methylxanthines) | Cat | About 20 mg/kg mild; 40–50 mg/kg cardiotoxic; 60 mg/kg and above seizures; LD50 100–200 mg/kg | The cat calculator grades against the same Merck bands as the dog one |
| Milk chocolate, rule of thumb | Dog | About 1 oz per lb of body weight is potentially lethal | Rule of thumb from the same Merck source, quoted in the dog calculator's FAQ |
| White chocolate | Dog | About 1 mg theobromine per oz (negligible) | The fat and sugar can still cause vomiting or pancreatitis in a small dog |
| Theobromine content used by the dog calculator | Dog | Milk 57, semisweet 136, dark 70–85% 227, baker's 364, cocoa powder 808 mg per oz | Per-ounce content values multiplied by the amount eaten; not doses |
| Theobromine content used by the cat calculator | Cat | White 0.04, milk 2.3, semisweet or dark 5.5, baker's 15.5, cocoa powder 28.5 mg per g | The cat calculator measures chocolate in grams rather than ounces |
| Onion, raw, cooked or dried | Dog | 15–30 g/kg: reported clinical-signs range | 1.5–3% of body weight; about one medium onion (150 g) for a 10 kg dog |
| Onion, raw | Cat | From about 5 g/kg | The site notes cats are affected at roughly a third of the canine dose |
| Garlic | Dog | 3–5× more toxic than onion (the calculator counts it at 4×) | Its worked example swaps a 150 g onion for 600 g of onion-equivalent garlic; chives, leeks and shallots count too |
| Grapes, raisins, sultanas, Zante currants | Dog | More than 1 grape or raisin per 4.5 kg (10 lb) of body weight may pose a renal risk | A risk reference, not a safe line: no established safe dose exists |
| Grapes or raisins, lowest documented toxic dose | Dog | 0.32–0.65 oz/kg | About 181–369 g for a 20 kg dog; case reports describe injury below this range |
| Xylitol in sugar-free products | Dog | No numeric dose is published on this site | Named as a cause of hypoglycaemia and liver failure; read the ingredients list |
Download: Toxic doses quick reference for dogs and cats (CSV, 15 rows): the same numbers as the table, for your own spreadsheet.
If an ingestion is suspected, contact your veterinarian or an emergency poison line immediately: do not wait to do the math. The numbers in this table are for reading, not dosing, and nothing here tells you how much of anything to give. The site lists two 24/7 numbers: ASPCA Animal Poison Control Center (888) 426-4435 and Pet Poison Helpline 1-888-213-6680, both with consultation fees that may apply. Never induce vomiting at home unless a veterinary professional tells you to, and take the wrapper, the amount eaten, the weight and the time of ingestion to the clinic.
The bands are population figures from the Merck Veterinary Manual as the calculators quote them. Individual sensitivity varies, an empty stomach speeds absorption, and pre-existing heart or kidney disease lowers the margin, so treat every value here as triage rather than diagnosis. The chocolate content values are averages from USDA and FDA composition data, and real products differ from them.
Grapes and raisins have no established safe dose anywhere in this site's guidance: the per-piece figure is a risk reference and the documented range records harm that has already been seen. Xylitol appears on this site only as an ingredient to avoid, so no dose is given for it here. Onion and garlic damage arrives late, with anaemia typically showing 3–5 days after ingestion, which is why those rows end in a phone call rather than a wait.
How this table was checked
Every row was copied from the calculator page that publishes it, then checked against that page's own source line; the emergency numbers come from the same pages' callouts. The CSV download is generated from the same rows as the table above. Last verified .
Sources
Every number in the table above traces to one of these 6 references.
- Merck Veterinary Manual: Chocolate Toxicosis in Animals (used for: The 20, 40–50, 60 mg/kg bands and LD50 100–200 mg/kg for dogs and cats, the 1 oz per lb rule of thumb, and the theobromine content values.)
- Merck Veterinary Manual: Garlic and Onion (Allium spp) Toxicosis in Animals (used for: 15–30 g/kg of raw onion producing clinical signs in dogs, cats from about 5 g/kg, and garlic being 3–5× more toxic.)
- Merck Veterinary Manual: Grape, Raisin, and Tamarind Toxicosis in Dogs (used for: The reference of more than one grape or raisin per 4.5 kg of body weight, and kidney failure generally within 72 hours.)
- ASPCA Animal Poison Control Center (used for: The lowest documented toxic grape or raisin dose of 0.32–0.65 oz/kg, and the poison-control number used in the contact block.)
- Pet Poison Helpline (used for: The second 24/7 emergency number in the contact block, as listed on the cat chocolate toxicity calculator.)
- US FDA: Leave Chocolate Out of Rover's Celebrations (used for: The per-ounce theobromine content figures the dog chocolate calculator uses for each chocolate type.)
Dr. Chyrle Bonk, DVM: Veterinary Editor
Chyrle is a mixed-animal veterinarian in rural Idaho who has practised since 2010, with a particular emphasis on food-animal medicine and cattle alongside her companion-animal caseload. She reviews the…