What Is Ovide? Uses, Dosage, and What You Need to Know in 2026

If your doctor has prescribed Ovide, you may be looking for a simple explanation of what it is, how it works, and how to use it safely. This guide covers everything patients need to know about Ovide in plain language.

What Is Ovide?

Ovide is the brand name for malathion 0.5% topical lotion, a prescription medication used to treat head lice (Pediculus humanus capitis) and their eggs (nits). It belongs to a class of drugs called organophosphate pediculicides — meaning it kills parasites (like lice) by interfering with their nervous system.

Ovide was first approved by the FDA in 1982. A generic version (malathion lotion 0.5%) became available in 2009. Both the brand and generic are therapeutically equivalent.

What Is Ovide Used For?

Ovide is FDA-approved to treat head lice infestations in patients 6 years and older. It is typically prescribed as a second-line or third-line treatment when over-the-counter options like permethrin (Nix) or pyrethrin-based products (Rid) have not worked. This is increasingly common as many lice populations have developed resistance to those first-line agents.

Ovide is also used off-label as an alternative treatment for pubic lice (per CDC guidelines). Both the American Academy of Pediatrics (AAP) and the CDC recognize malathion as an approved option for treatment-resistant head lice in school-age children and adults.

What Makes Ovide Different from Other Lice Treatments?

Two features set Ovide apart from many other lice treatments:

It's both pediculicidal AND ovicidal. It kills live lice AND their eggs (nits). Many OTC treatments (like permethrin 1%) are not reliably ovicidal — they kill live lice but leave eggs alive, requiring a second treatment 7-10 days later. Ovide kills both in one application.

It works on resistant lice. Malathion uses a different mechanism of action than pyrethroids, so it remains effective against lice that have developed resistance to permethrin-based products.

How to Use Ovide: Step-by-Step Instructions

Start with DRY hair. Do not wet your hair before applying — Ovide must be applied to dry hair only.

Apply enough to wet the hair and scalp. Use just enough lotion to thoroughly wet the hair and scalp. Pay special attention to the back of the head and neck where lice often congregate.

Wash your hands immediately. Wash hands thoroughly after applying to prevent accidental transfer to eyes or mouth.

Let hair air-dry naturally. DO NOT use a hair dryer or any heat source. Do not cover hair. The lotion is flammable.

Leave on for 8-12 hours. Most patients apply before bedtime and shampoo in the morning.

Shampoo and rinse. After 8-12 hours, shampoo hair and rinse thoroughly. Use a fine-toothed nit comb to remove dead lice and eggs.

Check for live lice after 7-9 days. If live lice are still present after 7-9 days, repeat the treatment one more time. Further treatment is generally not necessary.

Dosage and Formulation

Ovide comes in one form: a 0.5% topical lotion in a 59 mL (2 fl oz) bottle. The maximum amount for a single application is 2 fl oz. There is no weight-based dosing — use only enough to wet the hair and scalp. The formulation contains malathion 0.5% (5 mg/mL) in a vehicle of isopropyl alcohol (78%), terpineol, dipentene, and pine needle oil.

Who Should NOT Use Ovide?

Neonates and infants — contraindicated due to increased scalp permeability

Children under 6 years — safety and efficacy not established in well-controlled trials

People allergic to malathion or any vehicle ingredient (isopropyl alcohol, terpineol, dipentene, pine needle oil)

Pregnant women: should only be used when clearly needed (Pregnancy Category B); use caution when applying on another person if you are pregnant

How to Find Ovide at a Pharmacy

Ovide is not always easy to find at retail pharmacies because it's a niche prescription product. Use medfinder to locate pharmacies near you that can fill your prescription. For more detail, see: How to Find Ovide in Stock Near You