Ivermectin is used to treat strongyloidiasis (threadworm; infection with a type of roundworm that enters the body through the skin, moves through the airways and lives in the intestines). Ivermectin is also used to control onchocerciasis (river blindness; infection with a type of roundworm that may cause rash, bumps under the skin, and vision problems including vision loss or blindness). Ivermectin is in a class of medications called anthelmintics. It treats strongyloidosis by killing the worms in the intestines. It treats onchocerciasis by killing the developing worms. Ivermectin does not kill the adult worms that cause onchocerciasis and therefore it will not cure this type of infection.
Ivermectin comes as a tablet to take by mouth. It is usually taken as a single dose on an empty stomach with water. If you are taking ivermectin to treat onchocerciasis, additional doses 3, 6, or 12 months later may be necessary to control your infection. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take ivermectin exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
If you are taking ivermectin to treat strongyloidiasis, you will need to have a stool exam at least three times during the first 3 months after your treatment to see if your infection has cleared. If your infection has not cleared, your doctor will probably prescribe additional doses of ivermectin.
Ivermectin is also sometimes used to treat certain other roundworm infections, head or pubic lice infestation, and scabies (itchy skin condition caused by infestation with small mites that live under the skin). Talk to your doctor about the risks of using this medication for your condition.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
Before taking ivermectin,
- tell your doctor and pharmacist if you are allergic to ivermectin or any other medications.
- tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention if you are taking medications for anxiety, mental illness or seizures; muscle relaxants; sedatives; sleeping pills; or tranquilizers. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor if you have or have ever had meningitis, human African trypanosomiasis (African sleeping sickness; an infection that is spread by the bite of the tsetse fly in certain African countries), or conditions that affect your immune system, such as human immunodeficiency virus (HIV).
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant during your treatment with ivermectin, call your doctor.
- ask your doctor about the safe use of alcoholic beverages while you are taking ivermectin.
- if you are taking ivermectin for onchocerciasis, you should know that you may experience dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.if you are taking ivermectin for strongyloidiasis and have had loiasis (Loa loa infection with a type of worm that causes skin and eye problems) or if you have ever lived in or traveled to areas of West or Central Africa where loiasis is common, you should know that you may have a serious reaction. Call your doctor immediately if you experience blurred vision, head or neck pain, seizures or difficulty walking or standing.
Unless your doctor tells you otherwise, continue your normal diet.
Ivermectin is usually taken as a single dose. Tell your doctor if you do not take your medication.
Ivermectin may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- loss of appetite
- stomach pain or bloating
- uncontrollable shaking of a part of the body
- chest discomfort
If you are taking ivermectin to treat onchocerciasis, you may also experience the following side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- swelling of the eyes, face, arms, hands, feet, ankles, or lower legs
- joint pain and swelling
- painful and swollen glands of the neck, armpit or groin
- rapid heartbeat
- eye pain, redness, or tearing
- swelling of the eye or eyelids
- abnormal sensation in the eyes
Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:
- blistering or peeling skin
Ivermectin may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.
Symptoms of overdose may include:
- tingling of hands or feet
- loss of coordination
- stomach pain
- shortness of breath
- swelling of the face, arms, hands, feet, ankles, or lower legs
Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to ivermectin.
Do not let anyone else take your medication. Your prescription is probably not refillable.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Last Reviewed: September 1, 2010.