Generic name: ivermectin (oral) [ EYE-ver-MEK-tin ]
Brand name: Stromectol
Drug class: Anthelmintics

Medically reviewed by Melisa Puckey, BPharm. Last updated on Jun 12, 2025.

What is ivermectin?

Ivermectin is an anti-parasite medication used to treat parasitic diseases, including parasitic worms, hookworm, whipworm, and external parasites. Ivermectin tablets (Stromectol) are FDA-approved to treat strongyloidiasis of the intestinal tract and onchocerciasis (river blindness). Ivermectin cream (Soolantra) is FDA-approved to treat rosacea, and ivermectin lotion (Sklice) is a treatment for head lice.

Ivermectin tablets have also been used off-label for scabies and other parasites.

Ivermectin works by paralyzing muscles in parasites, causing them to die. Ivermectin mechanism of action in parasites is by binding to glutamate-gated chloride channels (GluCl), causing paralysis. It does not affect mammals as it is unable to enter the mammal's central nervous system, where the GluCl channels are located. Ivermectin tablets are also thought to help the human immune response to being able to overcome immature worms and kill them. It is thought that ivermectin tablets may suppress the ability of the parasite to secrete proteins that help it to evade the host’s natural immune defence mechanism.

Ivermectin and COVID-19 Treatment

Ivermectin is not FDA-approved for treating or preventing COVID-19 infection, and the FDA has reported “that currently available clinical trial data do not demonstrate that ivermectin is effective against COVID-19 in humans.”

The CDC does not list ivermectin tablets in Types of COVID-19 Treatment.

The World Health Organization (WHO) does not recommend ivermectin tablets for COVID-19 except in clinical trials.

In the clinical trial TOGETHER (NCT04727424), ivermectin tablets did not lower admission to a hospital due to progression of COVID-19 or prolonged emergency department observation among outpatients with an early diagnosis of COVID-19,  at high risk for serious illness, according to a National Institutes of Health article.

Adverse effects associated with ivermectin misuse and overdose have been reported. In some cases, people have taken veterinary products intended for use in large animals such as horses, sheep, and cattle. These products are highly concentrated and may result in overdoses when used by humans. DO NOT TAKE IVERMECTIN PRODUCTS INTENDED FOR ANIMAL USE.

Ivermectin side effects

Common side effects of ivermectin

Common ivermectin side effects may include:

• headache, muscle aches;
• dizziness,
• nausea, diarrhea, or
• mild skin rash.

Serious ivermectin side effects

Get emergency medical help if you have signs of an allergic reaction to ivermectin tablets: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Other serious side effects may occur. Call your doctor at once if you have:

• eye pain or redness, puffy eyes, problems with your vision;
• severe skin rash, itching, or rash with pus;
• confusion, change in your mental status, balance problems, trouble walking;
• fever, swollen glands, stomach pain, joint pain, swelling in your hands or feet;
• fast heart rate, trouble breathing;
• loss of bladder or bowel control;
• neck or back pain, seizure (convulsions); or
• a light-headed feeling, like you might pass out.

This is not a complete list of side effects, and others may occur. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Related/similar drugs

Warnings

You will need to have a stool exam after taking ivermectin tablets to make sure the infection is gone. Some patients may need to take another dose of ivermectin to treat the infection.

Ivermectin tablets may make you feel dizzy. To lower the chance of feeling dizzy or passing out, rise slowly if you have been sitting or lying down. Be careful going up and down stairs.

Before taking this medicine

You should not use ivermectin tablets if you are allergic to it.

To make sure ivermectin is safe for you, tell your doctor if you have:

• liver or kidney disease; or
• cancer, HIV or AIDS, or other conditions that can weaken your immune system.

Pregnancy

It is not known whether ivermectin will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

Breastfeeding

Ivermectin can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Ivermectin should not be given to a child who weighs less than 33 pounds (15 kg).

How should I take ivermectin?

Take ivermectin tablets on an empty stomach, at least 1 hour before or 2 hours after a meal.

Ivermectin is usually given as a single dose. Take this medicine with a full glass of water.

To effectively treat your infection, you may need to take ivermectin again several months to a year after your first dose.

If you have a weak immune system (caused by disease or by using certain medicine), you may need to take more than one dose of ivermectin. Some people who have a weak immune system need to take this medicine on a regular basis. Follow your doctor's instructions.

To make sure this medicine is working, you may need to provide frequent stool samples.

Never take ivermectin in larger amounts, or for longer than recommended by your doctor. Follow all directions on your prescription label.

Store this medicine at room temperature away from moisture and heat.

Dosing information

Usual ivermectin dose for Onchocerciasis

Dose: 0.15 mg/kg orally once every 12 months
For the treatment of individual patients, retreatment may be considered at intervals as short as 3 months.
Dosage guidelines based on body weight:
15 to 25 kg: 3 mg orally one time
26 to 44 kg: 6 mg orally one time
45 to 64 kg: 9 mg orally one time
65 to 84 kg: 12 mg orally one time
85 kg or more: 0.15 mg/kg orally one time

Usual Adult Dose for Strongyloidiasis

Dose: 0.2 mg/kg orally once
In general, additional doses are not necessary. However, followup stool examinations should be performed to verify eradication of infection.
Dosage guidelines based on body weight:
15 to 24 kg: 3 mg orally one time
25 to 35 kg: 6 mg orally one time
36 to 50 kg: 9 mg orally one time
51 to 65 kg: 12 mg orally one time
66 to 79 kg: 15 mg orally one time
80 kg or more: 0.2 mg/kg orally one time

Usual Adult Dose for Ascariasis (off-label)

Dose:  0.2 mg/kg orally once

Usual Adult Dose for Cutaneous Larva Migrans (off-label)

Dose: 0.2 mg/kg orally once

Usual Adult Dose for Filariasis (off-label)

Dose: 0.2 mg/kg orally once

Study (n=26,000)
Mass treatment in Papua, New Guinea:
Bancroftian filariasis: 0.4 mg/kg orally once yearly (with a single annual dose of diethylcarbamazine 6 mg/kg), for 4 to 6 years

Usual Adult Dose for Scabies (off-label)

Dose: 0.2 mg/kg orally once, and repeated in 2 weeks
Ivermectin therapy may be combined with a topical scabicide.

Usual Pediatric Dose for Filariasis (off-label):

Study (n=26,000)
Mass treatment in Papua, New Guinea:
Bancroftian filariasis:
5 years or older: 0.4 mg/kg orally once yearly (with a single annual dose of diethylcarbamazine 6 mg/kg), for 4 to 6 years

What happens if I miss a dose?

Since ivermectin tablets are usually given in a single dose, you may not be on a dosing schedule. If you are on a schedule, take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up for the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What to avoid

Drinking alcohol can increase certain side effects of ivermectin.

What other drugs will affect ivermectin?

Other drugs may interact with ivermectin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.

Popular FAQ

More FAQ

• Can ivermectin be used to treat COVID-19?
• How long does it take for ivermectin to kill head lice?
• How long does it take for Sklice (ivermectin) to kill head lice?

View more FAQ

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer