Ivermectin is an antiparasitic medicine derived from avermectin, a compound produced by the soil bacterium Streptomyces avermitilis. It has been in human use since 1987, sits on the WHO Model List of Essential Medicines, and has been administered billions of times worldwide. Satoshi Ōmura isolated the organism and William C. Campbell developed the compound into a medicine; they shared the 2015 Nobel Prize in Physiology or Medicine for the work.
Ivermectin binds with high affinity to glutamate-gated chloride ion channels. These channels exist in the nerve and muscle cells of invertebrates — nematodes, insects and arachnids — but not in the mammalian peripheral nervous system. Binding opens the channel, chloride ions flood in, the cell hyperpolarises and the parasite is paralysed and dies.
This selectivity is the foundation of ivermectin's safety profile. Humans do have related glycine and GABA-gated chloride channels, but they sit inside the central nervous system, behind the blood-brain barrier. Ivermectin is actively pumped back out of the brain by P-glycoprotein, so under normal conditions it never reaches them in meaningful concentration.
Ivermectin is an antiparasitic. It is not an antibiotic — it has no meaningful activity against bacteria and does not work by any antibacterial mechanism. It is not an antiviral in any approved sense either, though it has shown in-vitro activity against several viruses at concentrations far above those reached with standard human dosing.
Because it is not an antibiotic, the usual concerns about antibiotic resistance do not apply in the same way, and there is no recognised bacterial resistance to it.
Oral ivermectin is FDA-approved for two indications: intestinal strongyloidiasis caused by Strongyloides stercoralis, and onchocerciasis, better known as river blindness, caused by Onchocerca volvulus.
Topical ivermectin has two separate approvals: 1% cream for the inflammatory lesions of rosacea, and 0.5% lotion for head lice.
Beyond formal approval, ivermectin is recommended by dermatology and infectious-disease guidelines for scabies, including crusted scabies, and is used at enormous scale in mass drug administration programmes for soil-transmitted helminths and lymphatic filariasis.
Ivermectin is effective against a broad range of nematodes and ectoparasites: Strongyloides stercoralis, Onchocerca volvulus, Sarcoptes scabiei (scabies mites), Pediculus humanus capitis (head lice), Demodex mites, Ascaris lumbricoides (roundworm), Wuchereria bancrofti (lymphatic filariasis), and Mansonella species.
It is notably less effective against hookworm and against Trichuris trichiura (whipworm), which is why combination therapy with albendazole is used in some deworming programmes. It has no activity against tapeworms or flukes, which require praziquantel instead.
Ivermectin has been studied for a range of conditions outside its approved indications, and the honest position differs by area. For COVID-19, large randomised controlled trials including TOGETHER, ACTIV-6 and PRINCIPLE, and Cochrane systematic reviews, did not find benefit on mortality, hospitalisation or time to recovery. It is not authorised for COVID-19 by the FDA, EMA or WHO.
For cancer, laboratory and animal studies have reported antiproliferative effects across several tumour cell lines. That work is preclinical. There are no completed phase 3 human trials showing clinical benefit, and ivermectin is not approved for any oncology indication anywhere in the world.
We set this out plainly because customers are entitled to know exactly what is established and what is not. See the safety guide for how dose relates to risk.
GMP-certified human formulations — tablets and 1% cream. Never veterinary products. Most USA orders ship within 1–7 business days.
View products and pricingOral ivermectin is FDA-approved for intestinal strongyloidiasis and onchocerciasis (river blindness). Topical forms are approved for rosacea (1% cream) and head lice (0.5% lotion). It is also guideline-recommended for scabies and used widely for soil-transmitted helminths and lymphatic filariasis.
No. Ivermectin is an antiparasitic. It has no meaningful antibacterial activity and does not work by any antibiotic mechanism, which is why there is no recognised bacterial resistance to it.
Since 1987. It has been administered billions of times worldwide, largely through mass drug administration programmes, giving it one of the largest real-world safety records of any medicine.
Satoshi Omura isolated Streptomyces avermitilis from soil and William C. Campbell developed avermectin into ivermectin. Their work transformed treatment of river blindness and lymphatic filariasis, and they shared the 2015 Nobel Prize in Physiology or Medicine.
It has no activity against tapeworms or flukes, which need praziquantel. It is also notably weaker against hookworm and whipworm, which is why albendazole is often combined with it in deworming programmes.