A homemade cocoa brownie can hold about 115 mg of methylxanthines (theobromine plus caffeine). Merck reports mild signs from about 20 mg/kg, heart effects at 40–50 mg/kg and seizures at 60 mg/kg or more, so a 10 lb dog can reach the mild-sign level from less than one brownie (about 0.8). Brownies made with cannabis, xylitol or macadamia nuts add their own risks. Call your vet, ASPCA (888) 426-4435 or Pet Poison Helpline (855) 764-7661.
Published dose reference: Merck Veterinary Manual — chocolate toxicosis in animals; Merck Veterinary Manual — THC toxicosis in dogs and cats; Merck Veterinary Manual — macadamia nut toxicosis in dogs.
How we estimate chocolate per brownie
These are assumptions, not measurements of your brownie. There are three reference points, most cautious first:
- Homemade with cocoa powder: about 115 mg per brownie. The Hershey's Best Brownies recipe uses 3/4 cup of cocoa for 16 brownies. USDA FoodData Central lists 1 cup of unsweetened cocoa powder at 86 g, so each brownie holds about 4 g of cocoa. Merck lists cocoa powder at about 807 mg of methylxanthines per ounce.
- Homemade with unsweetened baking chocolate: about 75 mg per brownie. The Baker's One Bowl Brownies recipe uses 4 oz of unsweetened chocolate for 24 brownies. This site uses about 450 mg/oz for baking chocolate (USDA), a little above Merck's 440 mg/oz.
- Store-bought brownies: about 45 mg per large square. USDA FoodData Central lists commercially prepared brownies at 78 mg of theobromine and 2 mg of caffeine per 100 g, and a large square at 56 g.
Fudge frosting, chocolate chips, "double chocolate" recipes and big bakery brownies can contain more. If you don't know the recipe, use the homemade cocoa figure.
Dose table by dog weight and number of brownies
Estimated methylxanthine dose for homemade cocoa brownies at about 115 mg each. Merck's guideposts are about 20 mg/kg for mild signs, 40–50 mg/kg for heart effects and 60 mg/kg or more for seizures.
Published dose reference: Merck Veterinary Manual — chocolate toxicosis in animals; Merck Veterinary Manual — THC toxicosis in dogs and cats; Merck Veterinary Manual — macadamia nut toxicosis in dogs.
| Dog weight | ½ brownie | 1 brownie | 2 brownies | 4 brownies | Brownies to ~20 mg/kg | Brownies to ~60 mg/kg |
|---|---|---|---|---|---|---|
| 5 lb / 2.3 kg | 25 mg/kg | 51 mg/kg | 101 mg/kg | 202 mg/kg | 0.4 | 1.2 |
| 10 lb / 4.5 kg | 13 mg/kg | 25 mg/kg | 51 mg/kg | 101 mg/kg | 0.8 | 2.4 |
| 20 lb / 9.1 kg | 6.3 mg/kg | 13 mg/kg | 25 mg/kg | 51 mg/kg | 1.6 | 4.7 |
| 40 lb / 18 kg | 3.2 mg/kg | 6.3 mg/kg | 13 mg/kg | 25 mg/kg | 3.2 | 9.5 |
| 80 lb / 36 kg | 1.6 mg/kg | 3.2 mg/kg | 6.3 mg/kg | 13 mg/kg | 6.3 | 19 |
Published dose reference: Merck Veterinary Manual — chocolate toxicosis in animals; Merck Veterinary Manual — THC toxicosis in dogs and cats; Merck Veterinary Manual — macadamia nut toxicosis in dogs.
These numbers are approximate and are not safe limits. A dog that ate less than the table shows can still get sick, and other ingredients may matter more than the chocolate.
Cannabis ("pot") brownies
If the brownies could contain marijuana or THC, tell your vet straight away, because it changes what they watch for. Merck reports mild signs in dogs from THC doses as low as 0.3–0.5 mg/kg. Signs usually start 1–2 hours after eating (up to 4 hours in a dog with an empty stomach) and settle within 1–3 days. The most common are lethargy, wobbliness and vomiting, and dogs may dribble urine. Deaths are extremely rare, but the two published dog deaths both involved baked goods made with marijuana butter (Meola et al., 2012). Cornell's College of Veterinary Medicine notes that edibles may also contain chocolate, xylitol or high-fat butter. See marijuana.
Published dose reference: Merck Veterinary Manual — chocolate toxicosis in animals; Merck Veterinary Manual — THC toxicosis in dogs and cats; Merck Veterinary Manual — macadamia nut toxicosis in dogs.
Other brownie ingredients that can be worse
- Xylitol (sugar-free, "keto" or diabetic brownies): Pet Poison Helpline warns it can cause life-threatening low blood sugar, even within 10–15 minutes, and acute liver failure. Check the label for xylitol or birch sugar. See xylitol.
- Macadamia nuts: Merck reports signs in dogs after about 2.4 g/kg, usually within 12 hours: weakness, vomiting, wobbliness, tremors and a high body temperature. See macadamia nuts.
- Walnuts and pecans: ASPCA notes these nuts are high in fat and can cause vomiting, diarrhea and possibly pancreatitis. Merck lists moldy walnuts as a source of tremor-causing mycotoxins.
- Raisins: uncommon in brownies, but ASPCA notes grapes and raisins can lead to kidney damage in dogs. See raisins.
- Fat and sugar: Merck notes that the high fat content of chocolate products may trigger pancreatitis in susceptible dogs.
Published dose reference: Merck Veterinary Manual — chocolate toxicosis in animals; Merck Veterinary Manual — THC toxicosis in dogs and cats; Merck Veterinary Manual — macadamia nut toxicosis in dogs.
Symptom timeline
- Within minutes to a few hours (if the brownie had THC or xylitol): Pet Poison Helpline notes xylitol can drop blood sugar within 10–15 minutes. THC signs usually start within 1–2 hours, or up to 4 hours on an empty stomach (Merck), and Cornell notes they can start within 30 minutes.
- Within 6–12 hours: Merck reports that chocolate signs usually start in this window. Early signs include thirst, vomiting, diarrhea, a swollen belly and restlessness.
- Higher doses: hyperactivity, a racing heart, tremors and seizures (Merck: heart effects at 40–50 mg/kg, seizures at 60 mg/kg or more).
- Up to 72 hours: Merck notes signs can last up to 72 hours in severe cases. Some poisonings show signs later than this. If in doubt, call your vet.
- Later on: vomiting, belly pain and not eating can be signs of pancreatitis from the fat.
Published dose reference: Merck Veterinary Manual — chocolate toxicosis in animals; Merck Veterinary Manual — THC toxicosis in dogs and cats; Merck Veterinary Manual — macadamia nut toxicosis in dogs.
What to do now
Dog poison control: phone numbers, fees and when to call.
- Work out how many brownies are missing, and keep the box, wrapper or recipe.
- Check whether the brownies could contain cannabis, xylitol, macadamia nuts or raisins, and tell your vet if they might.
- Use the calculator on this page with your dog's weight and the number of brownies.
- Call your vet or a poison hotline now, especially if the estimate is 20 mg/kg or more, your dog is small, or another risky ingredient may be present. Do not make your dog vomit unless a vet tells you to.
Published dose reference: Merck Veterinary Manual — chocolate toxicosis in animals; Merck Veterinary Manual — THC toxicosis in dogs and cats; Merck Veterinary Manual — macadamia nut toxicosis in dogs.
How vets treat brownie poisoning
Treatment depends on the dose, the time since eating and your dog's signs. For chocolate, Merck describes:
- Making the dog vomit with a veterinary drug, considered only when the dog still seems normal and ate recently (for example, within 2 hours).
- Activated charcoal, a single dose considered only for lethal exposures, because charcoal can upset sodium levels after chocolate.
- Supportive care for dogs with signs: anti-nausea drugs, medicines for tremors or seizures, heart-rhythm drugs, IV fluids to help flush the methylxanthines out, heart monitoring and temperature control.
For THC, Merck says vets consider decontamination only within 1 hour and only in dogs with no signs. Cornell adds that dogs already showing signs should not be made to vomit, because of the risk of breathing in vomit. Merck notes the outlook for THC is generally good with supportive care, and mild cases may be monitored at home.
Related pages
- Chocolate toxicity calculator — for bars, baking chocolate and cocoa
- Dog ate chocolate — full chocolate guide
- Dog ate chocolate chip cookies
- Dog ate marijuana or edibles
- Dog ate xylitol
When to call for help
Call your veterinarian promptly after a known or suspected ingestion. ASPCA Animal Poison Control Center is available at (888) 426-4435 and Pet Poison Helpline at (855) 764-7661. These poison-control lines may charge a consultation fee. If your dog collapses, has a seizure, struggles to breathe, cannot stand or has a swollen painful abdomen, seek emergency veterinary care immediately; do not delay transport to finish reading or calculating a dose.
Have the dog's weight, the product or plant name, the maximum possible amount and the ingestion time ready. Bring the packaging or a clear photograph. The information lookup linked on this page can organize details, but it does not replace a poison-control consultation or urgent treatment. Do not induce vomiting without veterinary advice. This reference summarizes published veterinary sources; it does not establish a diagnosis or claim a new veterinary review.