Ivermectin

Pronunciation: eye-ver-MEK-tin.

Generic name
ivermectin
Drug class
Antiparasitic agent (avermectin derivative); topical formulations also used for inflammatory/dermatological indications
Form
3 mg oral tablet (Stromectol/generics); 1% (10 mg/g) topical cream (Soolantra); 0.5% topical lotion (Sklice)
Route
Oral (tablet); topical (cream, lotion)
Legal status
Prescription-only (oral tablet in all 6 markets reviewed; topical Soolantra cream prescription-only in the US/UK; topical Sklice lotion available over-the-counter in the US)

Supply Rules Vary

Trade names by country: United States · United Kingdom · Canada · Australia · New Zealand

Australia: STROMECTOL (9) · Full directory

What ivermectin is and how it works

Ivermectin is a prescription antiparasitic medicine. Taken orally (as Stromectol or a generic 3 mg tablet), it is approved to treat specific parasitic worm infections -- intestinal strongyloidiasis and onchocerciasis (river blindness) in all 6 markets reviewed, plus lymphatic filariasis (microfilaraemia caused by Wuchereria bancrofti) and human sarcoptic scabies in the UK and New Zealand. Separately, topical ivermectin formulations are approved in the United States for inflammatory lesions of rosacea (Soolantra 1% cream) and for head lice (Sklice 0.5% lotion, available over-the-counter). Ivermectin does NOT carry an FDA boxed warning. (1) (2) (7)

Ivermectin has been the subject of widespread public discussion regarding COVID-19. To state this factually: no medicines regulator reviewed for this page -- the US FDA, the European Medicines Agency, Australia's Therapeutic Goods Administration, or New Zealand's Medsafe, each of which issued its own explicit public statement -- has approved or authorised ivermectin for the prevention or treatment of COVID-19. This is a separate matter from ivermectin's real, genuinely-approved uses for parasitic infections and certain skin conditions, described on this page. If you are considering ivermectin for any reason, discuss it with a prescriber who can confirm whether an approved use applies to your situation.

Mechanism of action: how ivermectin works

Ivermectin binds selectively and with high affinity to glutamate-gated chloride ion channels found in invertebrate nerve and muscle cells, increasing membrane permeability to chloride ions and causing paralysis and death of the parasite. Mammals do not have glutamate-gated chloride channels; ivermectin has low affinity for other mammalian ligand-gated channels and does not readily cross the intact mammalian blood-brain barrier, which underlies its selective antiparasitic action. (11) (8)

What ivermectin is used for

Intestinal strongyloidiasis (oral, all 6 markets)

Treatment of intestinal (nondisseminated) strongyloidiasis caused by the roundworm Strongyloides stercoralis, as a single weight-based oral dose (approximately 200 mcg/kg). (1) (5) (8) (11)

Onchocerciasis / river blindness (oral, all 6 markets)

Treatment of onchocerciasis caused by the parasite Onchocerca volvulus, as a single weight-based oral dose (approximately 150 mcg/kg). Ivermectin kills the immature microfilariae but has no activity against adult worms living in subcutaneous nodules, so surgical removal (nodulectomy) may still be needed; retreatment every 3-12 months is common in mass treatment campaigns. (1) (8) (11)

Lymphatic filariasis (oral -- United Kingdom and New Zealand only)

Treatment of microfilaraemia in patients with lymphatic filariasis caused by Wuchereria bancrofti. This is an approved indication in the UK and New Zealand labels reviewed but is NOT listed in the current US DailyMed label or the Health Canada monograph reviewed for this page. (5) (11)

Human sarcoptic scabies (oral -- United Kingdom and New Zealand only)

Treatment of human sarcoptic scabies with a confirmed diagnosis (in New Zealand, specifically after prior treatment has failed). This is NOT listed as an approved oral indication in the current US or Canadian sources reviewed for this page. (5) (11)

Rosacea (topical cream -- United States and United Kingdom)

Soolantra 1% cream is approved for topical treatment of inflammatory lesions of rosacea (papulopustular rosacea) in adults, applied once daily for up to 4 months. This is an entirely separate product and indication from the oral tablet. (3) (6)

Head lice (topical lotion -- United States)

Sklice 0.5% lotion is approved for treatment of head lice in patients 6 months of age and older, and is available over-the-counter in the US. This is a separate product and indication from both the oral tablet and Soolantra cream. (4)

Before taking ivermectin

Do not take / not appropriate for

  • Do not take ivermectin if you have had an allergic (hypersensitivity) reaction to it or any of its ingredients. (all confirmed markets) (1) (5) (11)
  • Do not use ivermectin -- in any formulation, at any dose -- to try to prevent or treat COVID-19. No regulator among the FDA, EMA, TGA, or Medsafe has approved or authorised this use, and high, unapproved doses carry real risks including low blood pressure, seizures, and coma. (all confirmed markets) (2) (7) (10) (12)
  • Never take veterinary (animal) ivermectin products. These are formulated at much higher concentrations for large animals and are not safe for human use. (all confirmed markets) (2)

Tell your clinician about

  • If you live in, or have recently traveled from, a region of West or Central Africa where Loa loa (a different parasitic worm) is common, before oral treatment for onchocerciasis -- this affects your risk of a serious reaction.
  • If you weigh less than 15 kg -- safety of the oral tablet has not been established below this weight.
  • If you are pregnant, trying to become pregnant, or breastfeeding.
  • If you take warfarin or another blood-thinning medicine.
  • Any history of asthma, liver disease, or immune system problems.
  • If you are considering Soolantra cream while pregnant -- little human safety data exists for this use.
(1) (5) (11)

How to take ivermectin

  • Oral ivermectin (Stromectol/generic) is taken as a single dose on an empty stomach, with water, exactly as calculated by your prescriber based on your body weight and the condition being treated.
  • Do not take a second dose or repeat treatment on your own -- retreatment intervals for onchocerciasis or filariasis are set by your prescriber or a public health program.
  • Soolantra cream is applied once daily to affected facial areas, as directed, typically for up to 4 months.
  • Sklice lotion is applied to dry hair and scalp as directed on the label or by your prescriber, for head lice.
  • Do not use any ivermectin product for a use your prescriber has not confirmed is appropriate for you.
(1) (5) (11)

Procedures and treatment changes

Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)

Missed dose

Most oral ivermectin treatment is a single dose, or a dose given at a scheduled interval (such as every 6 or 12 months) as part of ongoing care for a parasitic infection -- there is no universal 'missed dose' rule to follow on your own. Contact your prescriber or the public health program managing your treatment for guidance if a scheduled dose was missed.

Overdose

Seek urgent medical attention or contact a poison control centre if too much ivermectin may have been taken, or if you develop severe rash, low blood pressure, seizures, unsteady movements, difficulty breathing, or loss of consciousness. No fatalities have been directly attributed to oral ivermectin overdose in the sources reviewed, but accidental exposure to concentrated veterinary formulations has caused rash, dizziness, nausea, vomiting, diarrhea, and rarely seizures or difficulty breathing. Management is supportive. (8) (11)

Side effects

Side effects and their urgency vary; report severe, persistent, or concerning symptoms.

Onchocerciasis treatment (Mazzotti-type reactions, common): pruritus (itching, up to 27.5%), skin reactions such as edema or rash (up to 22.7%), fever (up to 22.6%), and swollen lymph nodes (5-13.9%) -- these result from the death of microfilariae, not a direct drug side effect.

What to notice: Onchocerciasis treatment (Mazzotti-type reactions, common): pruritus (itching, up to 27.5%), skin reactions such as edema or rash (up to 22.7%), fever (up to 22.6%), and swollen lymph nodes (5-13.9%) -- these result from the death of microfilariae, not a direct drug side effect.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1) (11)

Strongyloidiasis treatment (generally mild): dizziness, itching, diarrhea, nausea, tiredness, abdominal pain, each reported in a small percentage of patients.

What to notice: Strongyloidiasis treatment (generally mild): dizziness, itching, diarrhea, nausea, tiredness, abdominal pain, each reported in a small percentage of patients.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (1)

Soolantra cream: skin burning sensation and irritation at the application site.

What to notice: Soolantra cream: skin burning sensation and irritation at the application site.

What to do: Discuss persistent or troublesome symptoms with the treating clinician or pharmacist. (6)

Serious warnings

Mazzotti reaction (onchocerciasis treatment) — high caution

Symptoms: Itching, hives/rash, red or painful eyes, joint or muscle pain, fever, swelling, swollen lymph nodes, and rarely more severe systemic or eye reactions -- caused by the death of microfilariae (the parasite's immature larvae) after treatment, not by the drug itself.

Action: This is an expected, monitored reaction in onchocerciasis treatment. Your prescriber may treat it with fluids, corticosteroids, antihistamines, or aspirin. Contact your prescriber promptly if reactions are severe. (1) (5) (11)

Serious or fatal encephalopathy in patients with heavy Loa loa co-infection — emergency

Symptoms: Severe headache, neck stiffness, red or painful eyes, bleeding in the eye, difficulty breathing, loss of bladder or bowel control, confusion or altered mental status, seizures, or coma.

Action: This risk is specific to onchocerciasis patients who are also heavily infected with Loa loa, a different parasitic worm found in parts of West and Central Africa. Your prescriber should assess for Loa loa co-infection before treatment if you are from or have traveled through an endemic area. Seek emergency medical attention immediately if these symptoms occur. (1) (5) (11)

Neurological toxicity without Loa loa infection — high caution

Symptoms: Reduced level of consciousness or coma, reported even in patients who do not have Loa loa co-infection.

Action: This is a separate, distinct finding from the Loa loa/encephalopathy risk above. These events have generally resolved with supportive medical care and stopping ivermectin. Seek medical attention immediately if this occurs. (5) (11)

Severe skin reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis) — emergency

Symptoms: Widespread blistering or peeling skin rash, mouth or eye sores, flu-like symptoms preceding a rash.

Action: Seek emergency medical attention immediately if these symptoms occur; ivermectin should be stopped only on the advice of the emergency medical team or your prescriber. (1) (5)

Bleeding or bruising while taking warfarin — moderate caution

Symptoms: Unusual bruising, bleeding, or blood in urine or stool.

Action: Tell your prescriber if you take warfarin -- rare post-marketing reports describe increased INR (a measure of blood clotting time) when the two are taken together. Your prescriber may want to monitor your INR more closely. (1) (11)

Interactions

  • Warfarin: rare post-marketing reports of increased INR when co-administered with ivermectin -- closer monitoring may be advised by your prescriber. (1) (11)
  • Diethylcarbamazine (DEC): concomitant use in mass filariasis treatment campaigns is not recommended in patients with high Loa loa microfilaraemia because of an increased reaction risk. (11)
  • Soolantra cream: ivermectin is metabolised by the CYP3A4 liver enzyme; caution advised with potent CYP3A4 inhibitors, which may increase systemic exposure even from a topical product. (6)
  • No formal oral drug-interaction studies have been performed for the oral tablet according to the UK SmPC reviewed -- known interactions are based on post-marketing reports rather than dedicated trials. (5)

Pregnancy, breastfeeding, kidney/liver function, age

Pregnancy

Oral ivermectin should not be used during pregnancy except when clearly necessary; animal studies showed teratogenic effects, though data from approximately 300 pregnancies exposed during mass onchocerciasis treatment campaigns (mostly first trimester) did not show an increase in birth defects, miscarriage, or infant death. Soolantra cream is not recommended in pregnancy; animal studies with oral ivermectin showed teratogenic effects, although topical absorption is not expected to be clinically significant. (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)

Breastfeeding

Ivermectin passes into breast milk at low concentrations (under 2% of the maternal dose for the oral tablet). Treatment during breastfeeding should only occur if the benefit outweighs the risk to the infant; some sources recommend delaying oral treatment until one week after childbirth if breastfeeding is planned. (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)

Children

Oral ivermectin's safety and effectiveness have not been established in children weighing less than 15 kg. Sklice lotion is approved for head lice from 6 months of age. Tablets may be crushed for children under 6 years in some markets per local labeling. (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)

Loiasis_coinfection

Patients being treated for onchocerciasis who are heavily co-infected with Loa loa are at increased risk of a serious, occasionally fatal encephalopathy -- pretreatment assessment is recommended for patients from Loa loa-endemic areas of West and Central Africa. (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)

Monitoring

Before starting

  • Assessment for Loa loa co-infection risk in patients from endemic West/Central African areas being treated for onchocerciasis
  • Body weight, to calculate the correct oral dose
  • Review of pregnancy status and breastfeeding plans
  • Review of current medicines, especially warfarin

During treatment

  • Monitoring for Mazzotti-type reactions after onchocerciasis treatment.
  • Monitoring for signs of encephalopathy in at-risk patients (heavy Loa loa co-infection).
  • Monitoring for reduced consciousness or neurological changes even without known Loa loa infection.
  • Monitoring INR in patients also taking warfarin.
  • Follow-up stool examination to confirm parasite eradication after strongyloidiasis treatment.
(1) (11)

Storage

Store the oral tablet below 30°C. Follow the storage instructions on the label for topical cream and lotion products. Keep out of reach of children.

Professional information

Clinician-facing context only, sourced from the current US, UK, EU, Canadian, Australian, and New Zealand sources reviewed; verify against the current full label before prescribing, and note the market-specific indication and COVID-19-authorisation differences described above.

United States

Indication: Oral: intestinal strongyloidiasis, onchocerciasis. Topical: rosacea (Soolantra), head lice (Sklice, OTC).

Dose summary: Oral: single dose ~200 mcg/kg (strongyloidiasis) or ~150 mcg/kg (onchocerciasis), weight-banded. No FDA boxed warning. Not approved for COVID-19.

Renal context: No specific renal dose adjustment identified in the reviewed label. (1) (3)

United Kingdom / European Union

Indication: Oral: strongyloidiasis, lymphatic filariasis (W. bancrofti), scabies. EU tablet authorisation is national per member state, not a single EMA centralised authorisation. Topical: rosacea (Soolantra).

Dose summary: Oral: single dose 200 mcg/kg (strongyloidiasis/scabies); 150-200 mcg/kg every 6 months or 300-400 mcg/kg annually for filariasis mass treatment. Not approved for COVID-19 in the EU (EMA explicit statement).

Renal context: No specific renal dose adjustment identified in the reviewed SmPC. (5) (7)

Canada, Australia, New Zealand

Indication: Canada: strongyloidiasis, onchocerciasis only (per reviewed monograph). Australia and New Zealand: strongyloidiasis, onchocerciasis, filariasis (NZ), scabies (NZ).

Dose summary: Same core dosing principle across all three: single weight-based oral dose, ~200 mcg/kg (strongyloidiasis/scabies) or ~150 mcg/kg (onchocerciasis). Not approved for COVID-19 in any of the three (TGA and Medsafe both issued explicit public statements).

Renal context: No specific renal dose adjustment identified in the reviewed sources. (8) (9) (11)

Mechanism of action

Overdose note

No fatalities directly attributed to oral ivermectin overdose have been reported in the sources reviewed. A study of healthy volunteers given up to 2000 mcg/kg fasted (roughly 10x the highest approved dose) or 600 mcg/kg with a high-fat meal showed no CNS toxicity at any dose. Management of suspected overdose is supportive. (11) (8)

Frequently asked questions

Is ivermectin approved to treat or prevent COVID-19?

No. As of this review, no regulator among the US FDA, the European Medicines Agency, Australia's TGA, or New Zealand's Medsafe -- each of which issued its own explicit public statement -- has approved or authorised ivermectin for the prevention or treatment of COVID-19. The FDA states that currently available data do not show ivermectin is effective against COVID-19, and warns that large or unapproved doses (including veterinary formulations) are dangerous. This is separate from ivermectin's real, approved uses for parasitic infections and certain skin conditions described on this page. (2) (7) (10) (12)

What is the Mazzotti reaction?

The Mazzotti reaction is a set of symptoms -- itching, hives, joint or muscle pain, fever, swelling, and swollen lymph nodes -- that can occur after ivermectin treatment for onchocerciasis (river blindness). It is caused by the body's response to dying microfilariae (immature parasite larvae), not a direct side effect of the drug itself. Your prescriber may treat it with fluids, antihistamines, corticosteroids, or aspirin. (1) (11)

What is the Loa loa risk, and is it the same as the other neurological warning?

No, these are two distinct, real findings. First, patients being treated for onchocerciasis who are also heavily co-infected with Loa loa (a different parasitic worm found in parts of West and Central Africa) have a real, serious, occasionally fatal risk of encephalopathy -- this is why prescribers assess for Loa loa exposure before treating patients from endemic areas. Second, and separately, reduced consciousness or coma has also been reported in some patients WITHOUT Loa loa co-infection, generally resolving with supportive medical care after stopping ivermectin. Both are genuine, verified findings from current regulator sources and are kept distinct here rather than combined into one warning. (5) (11)

Is oral ivermectin the same medicine as the ivermectin cream for rosacea?

They contain the same active ingredient but are different products with different approved uses, strengths, and routes of administration. The oral tablet (Stromectol/generics) treats parasitic infections. Soolantra is a 1% topical cream approved in the US and UK specifically for inflammatory lesions of rosacea. Sklice is a separate 0.5% topical lotion approved in the US for head lice. Using one product for another product's indication, or using a higher concentration than approved, is not supported by any regulator reviewed. (3) (4) (6)

Why is the oral tablet approved for filariasis and scabies in the UK and New Zealand but not in the US?

This is a real, verified difference between the labels actually reviewed for each market, not an error. The current US DailyMed label and the Health Canada product monograph reviewed list only strongyloidiasis and onchocerciasis as approved oral indications. The UK emc SmPC and the New Zealand Medsafe data sheet additionally list lymphatic filariasis (W. bancrofti microfilaraemia) and human sarcoptic scabies. Always confirm your local label's approved indications with your prescriber. (1) (5) (8) (11)

What is the mechanism of action of ivermectin?

Ivermectin binds selectively and with high affinity to glutamate-gated chloride ion channels found in invertebrate nerve and muscle cells, increasing membrane permeability to chloride ions and causing paralysis and death of the parasite. Mammals do not have glutamate-gated chloride channels; ivermectin has low affinity for other mammalian ligand-gated channels and does not readily cross the intact mammalian blood-brain barrier, which underlies its selective antiparasitic action. (11) (8)

What is the generic name of Ivermectin?

The generic name is ivermectin. (1) (11)

What class of drug is ivermectin?

Ivermectin is classed as: Antiparasitic agent (avermectin derivative); topical formulations also used for inflammatory/dermatological indications. (1) (11)

References

  1. STROMECTOL (ivermectin) tablets -- full prescribing informationU.S. Food and Drug Administration / DailyMed (NIH), full prescribing information, Merck Sharp & Dohme (Stromectol) and generic manufacturers · United States · accessed 2026-07-31 · source 1
  2. Why You Should Not Use Ivermectin to Treat or Prevent COVID-19U.S. Food and Drug Administration, official consumer update · United States · accessed 2026-07-31 · source 2
  3. Soolantra (ivermectin 1% cream) -- FDA approval for topical treatment of inflammatory lesions of rosaceaU.S. Food and Drug Administration, approval history · United States · accessed 2026-07-31 · source 3
  4. Sklice (ivermectin 0.5% lotion) -- prescription-to-OTC switch for head liceU.S. Food and Drug Administration approval history, reported via The Medical Letter · United States · accessed 2026-07-31 · source 4
  5. Ivermectin 3 mg tablets -- Summary of Product Characteristics (SmPC), PL 47587/0014 (Vygoris Limited)electronic medicines compendium (emc), United Kingdom · United Kingdom · accessed 2026-07-31 · source 5
  6. Soolantra 10 mg/g Cream -- Summary of Product Characteristics (SmPC)electronic medicines compendium (emc), United Kingdom -- Galderma (UK) Ltd · United Kingdom · accessed 2026-07-31 · source 6
  7. EMA advises against use of ivermectin for the prevention or treatment of COVID-19 outside randomised clinical trialsEuropean Medicines Agency (EMA) · European Union · accessed 2026-07-31 · source 7
  8. STROMECTOL (ivermectin tablet, USP) 3 mg -- Product Monograph Including Patient Medication InformationHealth Canada / Merck Canada Inc., Product Monograph · Canada · accessed 2026-07-31 · source 8
  9. STROMECTOL ivermectin 3mg tablet blister pack -- ARTG entry 181338Therapeutic Goods Administration (TGA), Australia · Australia · accessed 2026-07-31 · source 9
  10. TGA warns about imports of ivermectin / Risks of importing Ivermectin for treatment of COVID-19Therapeutic Goods Administration (TGA), Australia, official media release · Australia · accessed 2026-07-31 · source 10
  11. STROMECTOL ivermectin tablets -- New Zealand Data SheetMedsafe (New Zealand regulator) -- official New Zealand Data Sheet · New Zealand · accessed 2026-07-31 · source 11
  12. Risks of importing or prescribing ivermectin for prevention or treatment of COVID-19Medsafe (New Zealand regulator) and Ministry of Health, official safety alert · New Zealand · accessed 2026-07-31 · source 12

Brand names by country

Single-ingredient ivermectin names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.

Priority countries

United States

  • ivometn ivermectin lice treatment.5 g00g · shenzhen zhenshangzekai technology co., ltd.
  • STROMECTOL3 mg · merck sharp & dohme llc
  • Bldaxn Ivermectin Lotion0.5%.5 g00mL · guangzhou yusong fine chemicls co., ltd
  • Sklice5 mg/g · azurity pharmaceuticals
  • SOOLANTRA10 mg/g · galderma laboratories, l.p.
  • Head Lice Treatment Ivermectin Lotion118mL.005 g/mL · yunqi cosmetics (shenzhen) co., ltd
  • Scalp Care Lotions.005 g/mL · guangxi keyun e-commerce co., ltd.
  • RID One and Done5 mg/g · oystershell consumer health, inc.
  • SYNTHABIO Ivermectin.5 g00g · shenzhen xuyan technology co., ltd.
  • lice treatment dedicated.5 g00g · shenzhen zhenshangzekai technology co., ltd.

United Kingdom

  • Ivermectin 3 mg tablets (generic) (5)current licensed product · 3 mg tablet · Vygoris Limited, PL 47587/0014
  • Soolantra (6)current licensed product · 10 mg/g (1%) cream · Galderma (UK) Ltd

Canada

  • ROSIVER

Australia

  • STROMECTOL (9)current register product · 3 mg tablet · Merck Sharp & Dohme (Australia) Pty Ltd

New Zealand

  • STROMECTOL (11)current registered product · 3 mg tablet · See current Medsafe data sheet
View brands in additional countries.

European Union

Ivermectin (nationally authorised oral tablets, brand varies by member state) (7)

This page provides general reference information about ivermectin and is not a substitute for advice from the prescriber managing your treatment. Ivermectin has genuinely different approved uses depending on the formulation and country; it is not approved by any regulator reviewed for the prevention or treatment of COVID-19. All dosing and treatment decisions should be made with your prescriber.

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