Many people are aware that it is possible to induce vomiting in dogs by using hydrogen peroxide. But using hydrogen peroxide is not without potential complications, and there are alternatives.

Hydrogen peroxide works by creating enough irritation to the mouth, esophagus and stomach lining that vomiting occurs. Mild side effects to hydrogen peroxide ingestion can include continued vomiting or poor appetite. When this occurs, the patient is typically treated with antacids and stomach protectants until the gut has a chance to heal.

In rare cases, however, the side effects do not stop at mild irritation. Severe gastritis, or inflammation of the stomach, can occur, followed by ulceration and bleeding. Although very rare, pets have died from internal bleeding due to hydrogen peroxide toxicity.

Another potential but rare side effect of hydrogen peroxide ingestion is a gas emboli, an air clot in the blood vessels. Hydrogen peroxide will release oxygen when it reacts with tissue. This excess release of gas can be taken up by the inflamed stomach tissue, leading to this potentially fatal complication.

There are safer alternatives to using hydrogen peroxide to induce vomiting. Veterinarians will often give a medication called apomorphine to dogs, which is typically very effective in inducing vomiting. This medication is given through an IV. Alternatively, a small tablet can be placed under the lower eyelid for absorption. Rather than creating inflammation in the stomach, the drug stimulates the nausea centers of the brain and causes vomiting.

Ideally, if your dog has ingested something toxic, it is safer to bring him to the veterinarian than to induce vomiting at home. But there may be times when the risks of not inducing vomiting outweigh the risks of gastrointestinal irritation from hydrogen peroxide.

If your pet has ingested something extremely toxic, like rat poison, and you cannot bring your dog to a veterinary clinic in a timely manner, then using hydrogen peroxide would be a better choice then allowing that poison to be absorbed. Because there may be some emergency situations in which hydrogen peroxide is the better choice than not vomiting at all, it is important to know the proper way to use hydrogen peroxide.

The first thing to know is that you should never use hydrogen peroxide that is more concentrated then 3 percent. For example, 10 percent hydrogen peroxide is extremely corrosive to the gastrointestinal lining and should never be used.

The dose of 3 percent hydrogen peroxide is 1 milliliter per pound of dog. For example, a 20-pound dog would get 20 milliliters of hydrogen peroxide, or about 4 teaspoons.

If it has been more than 15 minutes after administration of the hydrogen peroxide and vomiting has not occurred, you may re-dose one more time. Do not continue to give your dog hydrogen peroxide if he is not vomiting. This could lead to an overdose and hydrogen peroxide toxicity. Not all dogs will vomit when given hydrogen peroxide.

There are times when it is contraindicated to induce vomiting — if, for example, your pet is seizing or extremely lethargic from the toxin he ingested. These animals are at high risk of aspirating the hydrogen peroxide.

There are some substances that pets eat where it is worse for it to come back up. If your pet has ingested sharp objects, inducing vomiting may create risk for getting these items lodged in the esophagus.

Also, it should be noted that you should never give hydrogen peroxide to a cat.

If your pet has ingested something that you think may be toxic, you should call your veterinarian or Pet Poison Helpline for advice at 1-855-764-7661. (Note that there is a fee for Pet Poison Helpline).

Sometimes, the substance that your pet has eaten has a mild enough effect or it was at a small enough dose that vomiting isn’t even necessary.