Ivermectin Side Effects
Commonly reported side effects of ivermectin include fever, pruritus, and skin rash. See below for a comprehensive list of adverse effects.
For the Consumer
Applies to ivermectin: oral tablet
In addition to its needed effects, some unwanted effects may be caused by ivermectin. In the event that any of these side effects do occur, they may require medical attention.
If any of the following side effects occur while taking ivermectin, check with your doctor or nurse as soon as possible:Less common—for the treatment of river blindness (onchocerciasis) only
- Eye or eyelid irritation, pain, redness, or swelling
Some of the side effects that can occur with ivermectin may not need medical attention. As your body adjusts to the medicine during treatment these side effects may go away. Your health care professional may also be able to tell you about ways to reduce or prevent some of these side effects. If any of the following side effects continue, are bothersome or if you have any questions about them, check with your health care professional: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
- swelling of the face, hands, arms, feet, or legs
- skin rash or itching
- Lightheadedness when getting up from a lying or sitting position
- Loss of appetite
- shaking or trembling
For Healthcare Professionals
Applies to ivermectin: compounding powder, oral tablet
Ivermectin is well tolerated compared to other microfilaricidal agents (i.e., thiabendazole, diethylcarbamazine). Adverse reactions (i.e., pruritus, fever, rash, myalgia, headache) occur commonly during the first 3 days after treatment and appear to be related to the extent of parasitic infection and systemic mobilization and killing of microfilariae. The majority of reactions can usually be treated with aspirin, acetaminophen and/or antihistamines. Adverse effects tend to occur with lesser frequency during periods of retreatment.[Ref]
Ocular side effects have included eyelid edema, anterior uveitis, blurred vision, conjunctivitis, limbitis, punctate opacity, keratitis, abnormal sensation in the eyes, and chorioretinitis/choroiditis; however, these effects are also associated with the disease onchocerciasis. Loss of vision has occurred rarely but usually resolved without corticosteroid treatment. Conjunctival hemorrhage has been reported during postmarketing experience in patients treated for onchocerciasis.[Ref]
Worsening of Mazzotti reactions, including arthralgia, synovitis, lymph node enlargement and tenderness, pruritus, skin involvement (including edema, papular and pustular or frank urticarial rash), and fever, has been reported during the first 4 days following treatment for onchocerciasis.
Nervous system side effects have included dizziness, headache, somnolence, vertigo, and tremor. Serious or fatal encephalopathy has been reported rarely in patients with onchocerciases, and heavily infected with Loa loa, either spontaneously or after treatment with ivermectin. Seizures have been reported during postmarketing experience.[Ref]
Gastrointestinal side effects have included anorexia, constipation, diarrhea, nausea, vomiting, and abdominal distention.[Ref]
Other side effects have included asthenia, fatigue, abdominal pain, chest discomfort, facial edema, and peripheral edema.
Hematologic side effects have included decreased leukocyte count (3%), eosinophilia (3%), and increased hemoglobin (1%). Hematomatous swellings associated with prolonged prothrombin times have been reported, but the clinical significance is unknown. Leukopenia and anemia have been reported in at least one patient.[Ref]
Hepatic side effects have included elevated ALT and/or AST. Elevated liver enzymes, elevated bilirubin, and hepatitis have been reported during postmarketing experience.[Ref]
Cardiovascular side effects have included tachycardia and orthostatic hypotension. EKG changes, including prolonged PR interval, flattened T waves and peaked T waves, have been reported in single cases. Hypotension (primarily orthostatic hypotension) has been reported during postmarketing experience.[Ref]
Dermatologic side effects have included pruritus, rash, and urticaria. Toxic epidermal necrolysis and Stevens-Johnson syndrome have been reported during postmarketing experience.
Respiratory side effects have included worsening bronchial asthma, laryngeal edema, and dyspnea.[Ref]
Musculoskeletal side effects have included myalgia.
Renal side effects have included rare transient proteinuria.[Ref]
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Not all side effects for ivermectin may be reported. You should always consult a doctor or healthcare professional for medical advice. Side effects can be reported to the FDA here.
More about ivermectin
- Other brands: Stromectol
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