In the U.S.—

In Canada—

• Anthelmintic, systemic

Ivermectin (eye-ver-MEK-tin) is used in the treatment of certain worm infections. It is used to treat river blindness (onchocerciasis) and a certain type of diarrhea (strongyloidiasis). It may also be used for some other kinds of worm infections.

Ivermectin appears to work by paralyzing and then killing the offspring of adult worms. It may also slow down the rate at which adult worms reproduce. This results in fewer worms in the skin, blood, and eyes.

Ivermectin is available only with your doctor's prescription, in the following dosage form:

Oral
• Tablets (U.S., Canada, Africa, Europe, and South America)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For ivermectin, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to ivermectin. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Ivermectin has not been studied in pregnant women and use of ivermectin is not recommended during pregnancy. Studies in animals given ivermectin have shown that ivermectin causes birth defects or other problems. Before taking this medicine, make sure your doctor knows if you are pregnant or if you may become pregnant.

Breast-feeding—Ivermectin passes into breast milk. However, it has not been reported to cause problems in nursing babies.

Children—Studies on this medicine have been done only in adults and in children weighing 15 kilograms (kg) (33 pounds) and over, and there is no specific information comparing use of ivermectin in children weighing less than 15 kg with use in other age groups.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of ivermectin in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

• Bronchial asthma—Ivermectin may make this problem worse.

Ivermectin is best taken as a single dose with a full glass (8 ounces) of water on an empty stomach (1 hour before breakfast), unless otherwise directed by your doctor.

To help clear up your infection, take this medicine exactly as directed. Your doctor may want you to take another dose every 3 to 12 months.

Your doctor may also prescribe a corticosteroid (a cortisone-like medicine) for certain patients with river blindness, especially those with severe symptoms. This is to help reduce the inflammation caused by the death of the worms. If your doctor prescribes these two medicines together, it is important to take the corticosteroid along with ivermectin. Take them exactly as directed by your doctor. Do not miss any doses.

Dosing—

The dose of ivermectin will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of ivermectin. If your dose is different, do not change it unless your doctor tells you to do so.

The time allowed between doses and the length of time you take the medicine depend on the medical problem for which you are taking ivermectin.

• For oral dosage form (tablets):
  • For river blindness:
    • Adults and teenagers—Dose is based on body weight and must be determined by your doctor. The usual dose is 150 micrograms (mcg) per kilogram (kg) (68 mcg per pound) of body weight as a single dose. The treatment may be repeated every three to twelve months.
    • Children—Dose is based on body weight and must be determined by your doctor. For children weighing 15 kg (33 pounds) or more, the usual dose is 150 mcg per kg (68 mcg per pound) of body weight as a single dose. If necessary, the treatment may be repeated every three to twelve months. For children weighing less than 15 kg, use and dose must be determined by your doctor.
  • For strongyloidiasis:
    • Adults and teenagers—Dose is based on body weight and must be determined by your doctor. The usual dose is 200 micrograms (mcg) per kilogram (kg) (91 mcg per pound) of body weight as a single dose. Additional doses usually are not needed.
    • Children—Dose is based on body weight and must be determined by your doctor. For children weighing 15 kg (33 pounds) or more, the usual dose is 200 mcg per kg (91 mcg per pound) of body weight as a single dose. For children weighing less than 15 kg, use and dose must be determined by your doctor.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

It is important that your doctor check your progress at regular visits. This is to help make sure that the infection is cleared up completely. In addition, if you have river blindness (onchocerciasis), your doctor may want you to have your eyes checked by an ophthalmologist (eye doctor). If you have a certain type of diarrhea (strongyloidiasis), your doctor may want to examine three stool samples. This should be done over the 3-month period following treatment.

If your symptoms become worse, check with your doctor.

This medicine may cause some people to become lightheaded. Make sure you know how you react to this medicine before you drive, use machines, or do anything else that could be dangerous if you are lightheaded. If these reactions occur, check with your doctor.

Before you have any medical tests, tell the medical doctor in charge that you are taking this medicine. The results of some tests (blood or liver tests) may be affected by this medicine.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• Less common—for the treatment of river blindness (onchocerciasis) only
  • Eye or eyelid irritation, pain, redness, or swelling 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome:

• More common—for the treatment of river blindness (onchocerciasis) only
  • Fever, itching or skin rash;  joint or muscle pain;  painful and tender glands in neck, armpits, or groin;  rapid heartbeat 
  
  

• Less common—for the treatment of river blindness (onchocerciasis) only
  • Headache;  swelling of the face, hands, arms, feet, or legs 
  
  

• Less common—for the treatment of strongyloidiasis only
  • Diarrhea;  dizziness;  skin rash or itching 
  
  

• Rare—for the treatment of river blindness (onchocerciasis) only
  • Lightheadedness when getting up from a lying or sitting position  
  
  

• Rare—for the treatment of strongyloidiasis only
  • Loss of appetite;  shaking or trembling ;  sleepiness 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

Once a medicine has been approved for marketing for a certain use, experience may show that it is also useful for other medical problems. Although these uses are not included in product labeling, ivermectin is used in certain patients with the following medical condition:

• Bancroft's filariasis
• Scabies

Other than the above information, there is no additional information relating to proper use, precautions, or side effects for these uses.