Ivermectin is the generic name of the prescription drug Stromectol, also available as a lotion (Sklice) and a cream (Soolantra).

Doctors prescribe ivermectin to treat parasites in the intestines, river blindness, scabies, and lice on the head and in the pubic area.

Ivermectin belongs to group of drugs known as antiparasitics. It works by increasing the amount of chloride that flows into the parasite's nervous system, which ultimately paralyzes and kills the parasite.

The Food and Drug Administration (FDA) first approved ivermectin under the brand name Stromectol in 1996. Merck Sharpe & Dohme manufactures it.

Ivermectin Warnings

You shouldn’t take ivermectin if you’re allergic to ivermectin or any ingredients in the drug.

Talk to your doctor before taking ivermectin if you have asthma or a skin condition called onychodermatitis.

Pregnancy and Ivermectin

Ivermectin has not been well studied in pregnant humans.

Before taking ivermectin, talk to your doctor about whether the drug benefits outweigh the potential risks to your unborn baby.

Whether or not ivermectin is for mothers who are breastfeeding has not been determined.

Tell your doctor if you’re pregnant, planning a pregnancy, or breastfeeding before taking ivermectin.

Ivermectin for Dogs and Cats

Veterinarians often prescribe ivermectin (under the brand names Heartgard, Ivomec, Iverhart, and others) for dogs and cats.

The drug is used to treat parasitic infections such as heartworm, mange, and ear mites.

Low doses of ivermectin are generally considered safe for animals.

However, ivermectin is not suitable for all dogs. Some carry a mutated gene (MDR-1) that makes the dog especially sensitive to ivermectin toxicity.

In dogs with this mutation, ivermectin can pass into the brain and nervous system with deadly consequences.

There are some dog breeds that are more sensitive to ivermectin than others. These include Australian and German Shepherds; English, Old English, and Shelton Sheepdogs; Syke Terriers; and Collies.

However, your dog's breed is not necessarily a guarantee that there will or will not be a problem with ivermectin.