Hydrogen peroxide dose to make a dog vomit

How much hydrogen peroxide do you give a dog to make it vomit?

The Merck Veterinary Manual gives 1 to 2 mL of 3% hydrogen peroxide per kg of body weight by mouth, up to a maximum of 45 mL (3 tablespoons) per dose, for use when veterinary care or prescription options aren't available. A veterinary toxicologist writing in Today's Veterinary Practice uses 2.2 mL/kg (1 mL per pound), with the same 45 mL cap; the familiar “1 teaspoon per 5 pounds” is about the same. The calculator shows Merck's range and never goes above 45 mL.

dose (mL) = weight in kg × 1 to 2, never more than 45 mL

Worked example: a 30 lb (13.6 kg) dog gets 13.6 to 27.2 mL, about 2.8 to 5.5 teaspoons. Any dog over about 50 lb hits the 45 mL cap.

Hydrogen peroxide dose chart for dogs

When you should never make a dog vomit

Vomiting can turn a bad situation into a worse one. Don't try it, and get to a vet instead, if any of these apply:

• Chewed a battery, or swallowed drain or oven cleaner, bleach, or another acid or alkali. Corrosive products can burn the food pipe again on the way back up. (A vet may handle a battery swallowed whole differently; that is their call.)
• Swallowed gasoline, kerosene, lamp oil, lighter fluid or another petroleum product. These are easily breathed into the lungs while vomiting.
• Already vomiting, drowsy, weak, trembling, unconscious or having a seizure. A dog that isn't fully alert can inhale vomit, and signs mean it needs a vet, not home treatment.
• Struggling to breathe or swallow. Without a normal swallowing reflex, vomit can go into the lungs.
• Flat-faced breed (pug, bulldog, Pekingese, boxer and similar). These breeds have a higher risk of inhaling vomit; see a vet first.
• Has heart or breathing disease. Vets list heart and respiratory disease as reasons not to induce vomiting.
• It was eaten more than 2 hours ago. Depending on the poison, vomiting may no longer help after 2 to 6 hours; ask the vet before trying.

The list comes from Merck's contraindications (no swallowing reflex, not neurologically stable, corrosives, hydrocarbons or petroleum products, high risk of inhaling vomit), plus warnings from Pet Poison Helpline and a veterinary toxicologist. When you call, the hotline will also weigh up what your dog ate: for some poisons, or after too long, vomiting won't help.

How to do it safely if a vet tells you to

1. Check the bottle says 3%. Stronger solutions, such as hair bleach products, can irritate the stomach and make it bleed.
2. Measure the dose the vet or hotline confirms with an oral syringe or measuring spoons. Don't guess with a cup.
3. Give it by mouth, slowly, and stay with your dog. Vomiting usually starts within 10 to 15 minutes.
4. If nothing happens after 10 to 15 minutes, call back. A second dose is sometimes advised; never give more without being told.
5. Keep your dog away from the vomit so it doesn't eat it again, and follow up with a vet even if it worked.

Risks of using hydrogen peroxide

Peroxide works by irritating the stomach, so some damage is part of how it works. Even at recommended doses, small bleeds can appear in the stomach lining, though they usually cause no signs. Too much, or too strong a solution, can seriously injure the food pipe, stomach and intestines. In one Pet Poison Helpline case, an owner gave a dangerous amount after a dog swallowed a human medicine; the pill came back up, but the dog kept vomiting, stopped eating and needed treatment for gut damage.

That's why toxicologists prefer vets to do it: they can use medicines that generally have fewer side effects and step in if something goes wrong. Home vomiting is a fallback when the clinic is far away and time matters, as it often does with grapes and raisins, chocolate or human painkillers. Not sure if what your dog ate is even dangerous? Check the is it toxic to dogs checker while you dial.