Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Stromectol

Descriptions


Ivermectin is used to treat river blindness (onchocerciasis), intestinal infection from threadworms (strongyloidiasis), and other kinds of worm infections.

Ivermectin is an anthelmintic. It works by interfering with the nerve and muscle functions of worms, by paralyzing and killing them.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

  • Tablet

Before Using

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 this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of ivermectin in children weighing less than 15 kilograms (kg). Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of ivermectin in the elderly. However, elderly patients are more likely to have age-related liver, kidney, or heart problems, which may require caution and an adjustment in the dose for patients receiving this medicine.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

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. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Warfarin

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Bronchial asthma—Use with caution. May make this condition worse.

Proper Use

Use this medicine exactly as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered. To do so may increase the chance of side effects.

It is best to take this medicine on an empty stomach. Swallow the tablet with water.

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.

Dosing

The dose of this medicine 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 this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (tablets):
    • For river blindness:
      • Adults and children weighing 15 kilograms (kg) or more—Dose is based on body weight and must be determined by your doctor. The dose is usually 150 micrograms (mcg) per kilogram (kg) of body weight taken as a single dose. The treatment may be repeated every 3 to 12 months. Each tablet contains 3 milligrams (mg) of ivermectin.
        • Weighing 85 kg or more—150 mcg/kg of body weight taken as a single dose.
        • Weighing 65 to 84 kg—4 tablets taken as a single dose.
        • Weighing 45 to 64 kg—3 tablets taken as a single dose.
        • Weighing 26 to 44 kg—2 tablets taken as a single dose.
        • Weighing 15 to 25 kg—1 tablet taken as a single dose.
      • Children weighing less than 15 kg—Use and dose must be determined by your doctor.
    • For threadworms:
      • Adults and children weighing 15 kilograms (kg) or more—Dose is based on body weight and must be determined by your doctor. The dose is usually 200 micrograms (mcg) per kilogram (kg) of body weight taken as a single dose. Each tablet contains 3 milligrams (mg) of ivermectin.
        • Weighing 80 kg or more—200 mcg/kg of body weight taken as a single dose.
        • Weighing 66 to 79 kg—5 tablets taken as a single dose.
        • Weighing 51 to 65 kg—4 tablets taken as a single dose.
        • Weighing 36 to 50 kg—3 tablets taken as a single dose.
        • Weighing 25 to 35 kg—2 tablets taken as a single dose.
        • Weighing 15 to 24 kg—1 tablet taken as a single dose.
      • Children weighing less than 15 kg—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions

It is important that your doctor check your or your child's progress at regular visits to make sure that the infection is cleared up completely. Blood tests may be needed to check for unwanted effects.

If you are being treated for river blindness, you may need retreatment and surgery to kill the adult parasite. You will need to see your doctor for follow up care.

If you are being treated for an intestinal infection from threadworms. You will need to have your bowel movements tested to make sure that the infection is gone. It is very important that you have these tests done as often as your doctor orders.

If your symptoms do not improve, or if they become worse, check with your doctor.

This medicine may cause eye, skin, or other serious reactions (eg, Mazzotti reaction), in patients treated for river blindness. Check with your doctor right away if you have eye or eyelid irritation, pain, redness, or swelling, dizziness, lightheadedness, fainting, fast, pounding, or irregular heartbeat or pulse, fever, itching or skin rash, joint or muscle pain, stomach pain, swelling of hands, ankles, feet, or lower legs, swollen, painful, or tender lymph glands in neck, armpit, or groin, unusual tiredness or weakness.

This medicine may cause serious brain and nerve problems. Check with your doctor right away if you have change in consciousness, confusion about identity, place, and time, decreased awareness or responsiveness, loss of consciousness, or severe sleepiness.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects

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 immediately if any of the following side effects occur:

More common

  1. Difficulty in moving
  2. muscle pain or stiffness
  3. pain in the joints
  4. swollen, painful, or tender lymph glands in the armpit

Less common

  1. Black, tarry stools
  2. bloating or swelling of the face, arms, hands, lower legs, or feet
  3. chest pain
  4. chills
  5. cold sweats
  6. cough
  7. dizziness or lightheadedness
  8. dizziness, faintness, or lightheadedness when getting up from lying or sitting position
  9. eye or eyelid irritation, pain, redness, or swelling
  10. fast, pounding, or irregular heartbeat or pulse
  11. feeling of constant movement of self or surroundings
  12. fever
  13. painful or difficult urination
  14. rapid weight gain
  15. sensation of spinning
  16. shakiness in the legs, arms, hands, or feet
  17. sore throat
  18. sores, ulcers, or white spots on the lips or in the mouth
  19. swollen glands
  20. tingling of the hands or feet
  21. trembling or shaking of the hands or feet
  22. trouble breathing
  23. unusual bleeding or bruising
  24. unusual sleepiness
  25. unusual tiredness or weakness
  26. unusual weight gain or loss

Rare

  1. Agitation
  2. back pain
  3. bloody eye
  4. blurred vision
  5. change in consciousness
  6. confusion
  7. decreased awareness or responsiveness
  8. difficulty in standing or walking
  9. hallucinations
  10. headache
  11. irritability
  12. loss of bladder control
  13. loss of bowel control
  14. loss of consciousness
  15. mood or mental changes
  16. redness of the eye
  17. seizures
  18. stiff neck
  19. unusual dullness or feeling of sluggishness
  20. vomiting

Incidence not known

  1. Blistering, peeling, or loosening of the skin
  2. burning, dry, or itching eyes
  3. change in consciousness
  4. confusion about identity, place, and time
  5. dark urine
  6. diarrhea
  7. discharge, excessive tearing
  8. light-colored stools
  9. loss of consciousness
  10. red skin lesion often with a purple center
  11. sensitivity of the eye to light
  12. swelling of the eyelids
  13. tearing
  14. upper right abdominal or stomach pain
  15. yellow eyes and skin

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

  1. Confusion about identity, place, and time
  2. decreased awareness or responsiveness
  3. severe sleepiness

Some 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. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

  1. Constipation
  2. lack or loss of strength
  3. loss of appetite
  4. stomach pain
  5. swelling or puffiness of the face

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

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Portions of this document last updated: Feb. 01, 2024

Original article: https://www.mayoclinic.org/ar/drugs-supplements/ivermectin-oral-route/side-effects/drg-20064397