Is Ivermectin an Antibiotic?

No. Ivermectin is not an antibiotic: it is an antiparasitic medicine in a drug class called anthelmintics, which are used for infections caused by parasitic worms. Mebendazole is not an antibiotic either; it is also an anthelmintic, while antibiotics are a separate group of medicines for infections caused by bacteria.

The mix-up is common, partly because ivermectin comes from a compound first found in a soil bacterium, and partly because many people use "antibiotic" to mean any medicine for an infection. This page explains what each kind of medicine is, how ivermectin and mebendazole are classified, and why the difference matters. It is general education, not medical advice.

What is an antibiotic?

MedlinePlus defines antibiotics as medicines that fight bacterial infections in people and animals. They are used for certain bacterial infections, such as strep throat, urinary tract infections and some E. coli infections. MedlinePlus is just as clear about what antibiotics are not for: they do not treat viral infections such as colds and runny noses.

Antibiotics are one part of a bigger family. The World Health Organization (WHO) uses the word antimicrobials for medicines that prevent and treat infectious diseases, and names four groups:

• Antibiotics, for bacteria
• Antivirals, for viruses
• Antifungals, for fungi
• Antiparasitics, for parasites

Each group is aimed at a different kind of organism. A medicine from one group is not a stand-in for a medicine from another.

Is ivermectin an antibiotic?

No. MedlinePlus places ivermectin in a class of medications called anthelmintics, which are anti-worm medicines. The prescribing information for the brand-name ivermectin tablet describes it the same way, as an anthelmintic taken by mouth.

Its labeled uses are two infections caused by parasitic worms:

• Intestinal strongyloidiasis, an infection with the roundworm Strongyloides stercoralis. See strongyloidiasis symptoms and treatment.
• Onchocerciasis, also called river blindness, caused by the worm Onchocerca volvulus. See onchocerciasis and river blindness.

Neither of these is a bacterial infection, and the prescribing information for ivermectin does not list any bacterial infection among its uses. You can read more in what is ivermectin.

Why people think ivermectin is an antibiotic

There is a real reason for the confusion. The prescribing information explains that ivermectin is derived from the avermectins, a group of antiparasitic compounds isolated from the fermentation products of Streptomyces avermitilis, a soil bacterium. Many familiar antibiotics also first came from soil microbes, so the two are easy to lump together.

Where a medicine comes from does not decide what it is used for. Ivermectin is made from a compound produced by a bacterium, but it is an antiparasitic, not a medicine for bacterial infections.

Is mebendazole an antibiotic?

No. MedlinePlus also places mebendazole in the anthelmintic class, and the prescribing information for the brand-name mebendazole chewable tablet calls it an anthelmintic. Its labeled uses are intestinal worm infections: pinworm, roundworm, whipworm and hookworm. Our guide to what mebendazole is covers those uses in more detail.

Is mebendazole an antimicrobial?

In the broad sense, yes. Because WHO counts antiparasitics as one of the four groups of antimicrobials, an anti-worm medicine such as mebendazole sits under that wide umbrella. It is still not an antibiotic, and its prescribing information does not cover any bacterial, viral or fungal infection.

Is ivermectin an antifungal or a steroid?

People ask about other drug classes too:

• Antifungal: neither ivermectin nor mebendazole is an antifungal. Fungal infections such as ringworm are treated with antifungal medicine; our page on pinworm vs ringworm explains that common mix-up.
• Steroid: ivermectin is not a steroid. Its prescribing information describes it as an anthelmintic.
• Antiviral: ivermectin is not classed as an antiviral, and its prescribing information does not list any viral infection among its uses.

Why the difference matters

Knowing which kind of medicine is which helps in a few practical ways:

• The medicine has to match the cause. An antibiotic is not used for a worm infection, and an anti-worm medicine is not used for a bacterial infection. That is why a clinician confirms the cause before choosing a medicine.
• Antibiotics are not for viruses. MedlinePlus notes that taking antibiotics when you do not need them can cause side effects and can contribute to antibiotic resistance, which is when bacteria change so that an antibiotic no longer stops them.
• Some combinations need care. The mebendazole prescribing information advises avoiding mebendazole together with metronidazole, an antimicrobial used for certain bacterial infections, because the combination has been linked with serious skin reactions (Stevens-Johnson syndrome and toxic epidermal necrolysis). See mebendazole side effects and drug interactions.

Always tell the prescriber about every medicine you take, including antibiotics, other prescriptions, over-the-counter products and supplements. A pharmacist can also check a combination for you.

Getting a prescription for an anti-worm medicine

Ivermectin and mebendazole both need a prescription in the United States. Get It Prescribed offers an online review by a licensed provider for people with a labeled reason to use one of them. You complete a written health assessment and pay a one-time $50 consultation fee, and the provider decides whether a prescription is appropriate. Ivermectin costs $3.00 per tablet and mebendazole costs $3.50 per capsule, and the prescriber decides the quantity. The service is available in all 50 states and the District of Columbia, and some states require a live phone or video visit. How it works walks through each step.

A prescription is never guaranteed. The ivermectin and mebendazole dispensed through Get It Prescribed are compounded preparations made by a licensed compounding pharmacy for an individual patient. Compounded preparations are not FDA-approved, and the FDA does not review them for safety, effectiveness or quality. They are not generics of, or substitutes for, the brand-name products.

If you think you have a bacterial infection, such as strep throat or a urinary tract infection, see your own clinician or an urgent care clinic. Get It Prescribed does not prescribe antibiotics.

Related questions

Is ivermectin an antibiotic or an antiparasitic?

It is an antiparasitic. Ivermectin is an antiparasitic medicine in the anthelmintic (anti-worm) class. Antibiotics are for bacterial infections. The labeled uses of ivermectin are two parasitic worm infections: intestinal strongyloidiasis and onchocerciasis (river blindness).

Is mebendazole an antibiotic?

No. Mebendazole is also an anthelmintic. Its labeled uses are intestinal worm infections: pinworm, roundworm, whipworm and hookworm. Its prescribing information does not cover any bacterial infection.

Why is ivermectin sometimes called an antibiotic?

Ivermectin is derived from the avermectins, compounds isolated from the fermentation products of a soil bacterium, Streptomyces avermitilis. Many antibiotics also came from soil microbes, which causes the mix-up, but ivermectin is an antiparasitic, not a medicine for bacterial infections.

Is mebendazole an antimicrobial?

In the broad sense, yes. The World Health Organization groups antibiotics, antivirals, antifungals and antiparasitics together as antimicrobials, so an antiparasitic such as mebendazole falls under that term. It is still not an antibiotic.

Can you take ivermectin or mebendazole with antibiotics?

It depends on the specific medicines, so tell your prescriber about everything you take. The mebendazole prescribing information advises avoiding mebendazole with metronidazole, because the combination has been linked with serious skin reactions. A pharmacist or prescriber can check any other combination.

Sources

• MedlinePlus: Ivermectin — consumer drug information; ivermectin is in the anthelmintic class.
• MedlinePlus: Mebendazole — consumer drug information; mebendazole is in the anthelmintic class.
• MedlinePlus: Antibiotics — what antibiotics are, what they treat, and why they are not used for viral infections.
• MedlinePlus: Metronidazole — consumer drug information; metronidazole is an antimicrobial used for certain bacterial infections.
• WHO: Antimicrobial resistance fact sheet — antimicrobials include antibiotics, antivirals, antifungals and antiparasitics.
• DailyMed: ivermectin tablet prescribing information — description as an anthelmintic derived from the avermectins, and labeled uses.
• DailyMed: mebendazole chewable tablet prescribing information — anthelmintic class, labeled uses and the metronidazole warning.
• FDA: Compounding and the FDA — Questions and Answers — what compounded preparations are and how they are regulated.