Key takeaways
- Ivermectin dosing is calculated based on body weight in kilograms (kg), with adults typically receiving 150 to 200 micrograms (mcg) per kg depending on whether the infection being treated is onchocerciasis or strongyloidiasis.
- Treatment for strongyloidiasis usually involves a single dose that completes the full course of therapy, while onchocerciasis typically requires repeated dosing every 3 to 12 months to manage the parasitic infection over time.
- Children weighing at least 15 kg can receive ivermectin at the same weight-based doses as adults, and the medication should always be taken with water on an empty stomach.
Ivermectin is a generic prescription oral tablet that may be taken just once or routinely, depending on your condition. It’s used in adults and certain children to treat the following types of infections caused by parasites:
- strongyloidasis, which may affect your intestines
- onchocerciasis, which may affect your skin and eyes
Ivermectin belongs to a group of drugs called antiparasitics.
Ivermectin comes as an oral tablet in one strength of 3 milligrams (mg).
The following table highlights the basics of ivermectin’s dosage.
| Condition | Usual recommended dose |
|---|---|
| strongyloidasis | one single dose |
| onchocerciasis | one dose every 3 to 12 months |
Your dosage will be based on your body weight in kilograms (kg). For reference, 1 kg is approximately equal to 2.2 pounds (lb).
What are the usual dosages of ivermectin in adults?
The following information describes dosages that are commonly used or recommended. But be sure to take the dosage your doctor prescribes for you. They’ll determine the best dosage to fit your needs.
Dosage for strongyloidasis
For adults with strongyloidasis, a single dose of ivermectin is usually taken. The amount of the drug you’ll take in that single dose is based on your body weight.
Your doctor may recommend a dosage of 200 micrograms (mcg) of ivermectin per kg of body weight. Your doctor may use the following dosage table to help prescribe your dose:
| Weight in kg | Number of tablets (3 mg each) |
|---|---|
| 15 to 24 kg | 1 tablet |
| 25 to 35 kg | 2 tablets |
| 36 to 50 kg | 3 tablets |
| 51 to 65 kg | 4 tablets |
| 66 to 79 kg | 5 tablets |
| 80 kg or more | 200 mcg per kg of body weight |
For example, if you weigh 68 kg (about 150 pounds [lb]), you’ll likely be prescribed a dose of 5 ivermectin tablets. Each tablet contains 3 mg, so your total dose would be 15 mg.
A single dose will likely be a complete course of treatment. Your doctor will recommend when to screen your stool to make sure the infection has been properly treated. You may need to provide a stool sample monthly for the first 3 months after you take your dose.
Dosage for onchocerciasis
For adults with onchocerciasis, the typical dosage of ivermectin is based on your weight in kg.
Your doctor may recommend a dosage of 150 mcg of ivermectin per kg of body weight. Your doctor may use the following dosage table to help prescribe your dose:
| Weight in kg | Number of tablets (3 mg each) |
|---|---|
| 15 to 25 kg | 1 tablet |
| 26 to 44 kg | 2 tablets |
| 45 to 64 kg | 3 tablets |
| 65 to 84 kg | 4 tablets |
| 85 kg or more | 150 mcg per kg of body weight |
For example, if you weigh 68 kg (about 150 lb), you’ll likely be prescribed 4 ivermectin tablets. Each tablet contains 3 mg, so your total dose would be 12 mg.
Most people receive a single dose every 12 months. But some people may need to receive a dose every 3 months. Your doctor will determine the dosing interval that’s right for you.
What’s the dosage of ivermectin for children?
Ivermectin is used to help treat strongyloidasis and onchocerciasis in children who weigh at least 15 kg (about 33 lb). The dosage used in these children is the same as the dosage for adults. To learn more, see the “What are the usual dosages of ivermectin in adults?” section.
For more information about ivermectin’s dosage for children, talk with your child’s doctor or a pharmacist.
How to take ivermectin
You’ll take your dose of ivermectin at home, with water but without food.
Is ivermectin used long term?
Whether ivermectin is used long term depends on your condition. In some cases, ivermectin is given as a single dose to provide a complete course of therapy. But in other cases, you’ll need to take this single dose at certain intervals. Talk with your doctor to learn more about how long you can expect to take ivermectin.
Do not take more ivermectin than your doctor prescribes, as this can lead to harmful effects.
Symptoms caused by an overdose can include:
- skin rash
- edema (swelling of your feet, legs, ankles, or other body parts caused by fluid retention)
- headache
- dizziness
- asthenia (weakness)
- nausea and vomiting
- diarrhea
What to do in case you take too much ivermectin
Call your doctor right away if you think you’ve taken too much ivermectin. You can also call 800-222-1222 to reach America’s Poison Centers or use its online resource. But if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.
Is the dosage of ivermectin the same when used in humans and dogs?
No. Ivermectin that’s prescribed for humans isn’t the same as the form that’s prescribed for animals, such as dogs. The dosages of each are also different.
Drugs for animals go through different regulatory processes than those prescribed for humans. This means that drugs for animals haven’t been studied in the same ways as drugs for humans.
Some people have taken ivermectin, including forms of the drug prescribed for animals, to treat or prevent COVID-19. But ivermectin isn’t Food and Drug Administration (FDA)-approved for these uses in humans (or animals).
Never take forms of ivermectin intended for animals. Doing so can cause serious side effects, especially if taken in high doses.
Is ivermectin used for scabies? If so, what’s the dosage?
Ivermectin isn’t approved by the FDA to treat scabies. Scabies is an infection that may cause a skin rash when you come in contact with a certain type of mite (Sarcoptes scabiei).
But in some cases, your doctor may prescribe ivermectin
Because ivermectin isn’t approved for scabies, the drug manufacturer doesn’t provide recommended dosages for this use. Your doctor will prescribe the dosage that’s right for you.
To learn more about your treatment options for scabies, talk with your doctor.
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