Is it safe to gargle iodine or inhale peroxide? This medical toxicologist says no

Man breathing with a nebulizer while on a laptop.

Why gargling iodine and inhaling peroxide can be dangerous

Two new COVID-19 claims are cause for concern. One claim is that inhaling hydrogen peroxide through a nebulizer will treat COVID-19. The other is that gargling with iodine will prevent COVID-19. 

Both of these rumors are dangerous, says the medical director of the Nebraska Regional Poison Center, Ron Kirschner, MD. Since he specializes in emergency medicine and medical toxicology, Dr. Kirschner often sees the real consequences of these online trends.

“There’s a lot of stuff on the internet that’s harmful or dangerous,” says Dr. Kirschner. “If you have something like vaccination, which has been shown to be effective in preventing serious disease from COVID-19, you should use that. Not these ineffective and harmful things that don’t prevent COVID-19. Use something that works.”

Gargling with iodine

Accidentally swallowing too much povidone iodine can cause a toxic reaction.

“Iodine is meant to disinfect surfaces, not to be used internally,” says Dr. Kirschner. “Using iodine internally can cause injury to your esophagus or to your gastrointestinal tract. It’s not going to be helpful and will do more harm than good.”

“You can use iodine to clean surfaces,” explains Dr. Kirschner. “It does a good job of eliminating bacteria and viruses on tabletops or countertops. But it’s very irritating and shouldn’t be used inside your body.” 

Even Betadine®, the manufacturer of first aid products that contain iodine, says the products do not prevent or treat COVID-19:

“Betadine® Antiseptic First Aid products should only be used to topically treat minor cuts, scrapes and burns. The first aid products should not be used as a gargle. Betadine Antiseptic products have not been demonstrated to be effective for the treatment or prevention of COVID-19 or any other viruses.” 

Inhaling hydrogen peroxide

“Using hydrogen peroxide through a nebulizer is a bad idea, because it’s an oxidizing agent that can cause direct tissue injury,” says Dr. Kirschner. “If you inhale it, it can be harmful to the bronchi in the lungs or your airways.”

Dr. Kirschner encourages you to consider vaccinations rather than these unproven, and potentially dangerous, ideas. “If you’re worried about COVID-19, you should get vaccinated, not do things that are harmful.” Ivermectin is another ineffective COVID-19 remedy that has landed people in the hospital after inappropriate use. It might be effective for treating parasites (intestinal worms, scabies), but there’s no evidence that it helps for COVID-19.

“Millions of people have used the vaccines,” Dr. Kirschner explains. “They’re safe. We haven’t seen a lot of people getting sick from the vaccines. We have seen a lot of people getting sick from COVID-19, and dying from COVID-19.”