Pediculosis capitis (head lice infestations) occur in all age groups, but especially in elementary school children. In most cases, transmission occurs by head-to-head contact. Pharmacologic treatment is recommended for persons with live lice or eggs (nits) within 1 cm of the scalp. Topical pediculicides should be tried first. Oral therapy is occasionally required for refractory infestations.

Topical ivermectin lotion 0.5% (Sklice, and generics), which has been available by prescription since 2012, is now FDA-approved for sale over the counter (OTC) for treatment of head lice in patients ≥6 months old. Ivermectin is also available by prescription as a 1% cream (Soolantra) approved for topical treatment of inflammatory lesions of rosacea and in oral tablets (Stromectol, and generics) for treatment of various parasitic infections.

Head lice infestation occurs in all age groups, but especially in elementary school children. In most cases, transmission occurs by head-to-head contact.

The FDA has approved the antiparasitic drug ivermectin in a 0.5% lotion (Sklice – Sanofi Pasteur) as a single-use topical treatment for head lice in patients ≥6 months old. Oral ivermectin (Stromectol – Merck) is effective for treatment of head lice resistant to other therapies, but it has not been approved by the FDA for this indication.

The FDA has approved spinosad 0.9% suspension (Natroba – ParaPro) for topical treatment of head lice infestation in patients ≥4 years old. It is available only by prescription.

The FDA has approved benzyl alcohol lotion, 5% (Ulesfia Lotion - Sciele) for treatment of head lice in patients ≥6 months old. The active ingredient is 5% benzyl alcohol; the vehicle is 5% mineral oil.

Head lice occur in all age groups, but especially in elementary school children during the winter months. Infestations are becoming more difficult to treat because of increasing resistance to the chemical pediculicides commonly used, particularly those that are available over-the-counter (OTC).

Parasitic infections are found throughout the world. With increasing travel, immigration, use of immunosuppressive drugs and the spread of AIDS, physicians anywhere may see infections caused by previously unfamiliar parasites. The table below lists first-choice and alternative drugs for most parasitic infections. The brand names and manufacturers of the drugs are listed in this article.

Superseded--purchase updated Parasitic Infections article
Parasitic infections are found throughout the world. With increasing travel, immigration, use of immunosuppressive drugs and the spread of AIDS, physicians anywhere may see infections caused by previously unfamiliar parasites.

Note: Drugs for Parasitic Infections, revised and updated, is now available to both subscribers and nonsubscribers on our web site. This article, a bi-annual feature of The Medical Letter for many years, will not be published as a printed issue in 2002, but is included in the 16th edition of The Medical Letter Handbook of Antimicrobial Therapy. The handbook is now available and can be ordered by calling customer service at 1-800-211-2769.

0.5% malathion in 78% isopropanol was recently approved by the FDA for treatment of head lice.

Several readers have asked the Medical Letter to review the treatment of head lice, which apparently have become increasingly resistant to recommended drugs (KY Mumcuoglu, American Entomologist, Fall 1996, page 175). Assays for drug resistance of head lice have not been standardized, however, and poor technique, such as not using a louse comb after treatment to remove lice and nits (eggs), may be responsible for some treatment failures. The last Medical Letter article on treatment of parasitic infections (vol. 37, page 99, November 10, 1995) recommended 1% permethrin (Nix) or 0.5% malathion (Prioderm; Ovide) as the drug of choice for treatment of head lice and pyrethrins with piperonyl butoxide (Rid, and others) as an alternative.