The FDA has approved a 0.25% ophthalmic solution of the ectoparasiticide lotilaner (Xdemvy – Tarsus) for treatment of Demodex blepharitis. Lotilaner is the first drug to be approved in the US for this indication.

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.

Rosacea is a common, chronic inflammatory facial eruption of unknown cause. It is more prevalent in women than in men, and disease onset typically occurs after age 30. Rosacea is characterized by erythema, telangiectasia, and flushing, and sometimes by recurrent, progressive crops of acneiform papules and pustules, usually on the central part of the face. Some patients develop granulomas and tissue hypertrophy, which may lead to rhinophyma (a bulbous nose), particularly in men. Blepharitis and conjunctivitis are common. Keratitis and corneal scarring occur rarely.

View the Comparison Table: Some Topical Drugs for Rosacea

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.

Results from a double-blind trial suggest that off-label use of the oral antihyperglycemic drug metformin in patients with COVID-19 may decrease the risk of post-acute sequelae of SARS-CoV-2 infection ("long COVID").

Epsolay (Galderma), a 5% benzoyl peroxide cream, has been approved by the FDA for treatment of inflammatory lesions of rosacea in adults. It is the first product containing benzoyl peroxide to be approved in the US for treatment of rosacea. Benzoyl peroxide formulations approved for acne have been used off-label to treat rosacea for years, but itching and burning have limited their use.

This article includes recommendations for management of most sexually transmitted infections (STIs) other than HIV and viral hepatitis. Some of the indications and dosages recommended here have not been approved by the FDA (see Table 1).

On April 29, the NIH recommended against use of the antiparasitic drug ivermectin for treatment of COVID-19 outside of a clinical trial. The recommendation was made because recent randomized, placebo-controlled trials of ivermectin have produced negative results and because alternative drugs that have been shown to be effective for treatment of COVID-19 are available.

The FDA has approved a 1.5% topical foam formulation of minocycline (Zilxi – Foamix) for treatment of inflammatory lesions of rosacea in adults. It is the only topical minocycline product approved for this indication. The same manufacturer markets minocycline foam 4% (Amzeeq) for treatment of acne in patients ≥9 years old.

View the Table: Treatments Considered for COVID-19

The text and tables that follow include recommendations for management of sexually transmitted infections (STIs) other than HIV and viral hepatitis. Some of the indications and dosages recommended here have not been approved by the FDA.

The FDA has approved the selective alpha_1A-adrenergic receptor agonist oxymetazoline as a 1% cream (Rhofade – Allergan) for topical treatment of persistent facial erythema of rosacea in adults. Brimonidine, a selective alpha₂-adrenergic receptor agonist, was approved in 2013 as a 0.33% gel (Mirvaso) for the same indication. Like Mirvaso, Rhofade is not indicated for treatment of inflammatory lesions of rosacea. Oxymetazoline has been available over the counter for many years as a nasal decongestant spray (Afrin, and others).

View the Comparison Table: Some Topical Drugs for Rosacea

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

This common, chronic inflammatory facial eruption of unknown cause is more prevalent in women than in men. Rosacea is characterized by erythema and telangiectasia, and sometimes by recurrent, progressive crops of acneiform papules and pustules, usually on the central part of the face. Some patients develop granulomas and tissue hypertrophy, which may lead to rhinophyma (a bulbous nose), particularly in men. Blepharitis and conjunctivitis are common. Keratitis and corneal scarring occur rarely.

The FDA has approved a 1% cream formulation of the antiparasitic drug ivermectin (Soolantra – Galderma) for topical treatment of inflammatory lesions of rosacea. Ivermectin is available in the US in tablets (Stromectol, and generics) for treatment of onchocerciasis and other worm infestations and as a 0.5% lotion (Sklice) for treatment of head lice.

Many infections can be transmitted during sexual contact. The text and tables that follow include recommendations for management of sexually transmitted infections (STIs) other than HIV, viral hepatitis, and enteric infections. Some of the indications and dosages recommended here have not been approved by the FDA.

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.

Many infections can be transmitted during sexual contact. The text and tables that follow are limited to management of sexually transmitted infections (STIs) other than HIV, viral hepatitis and enteric infections. The drugs of choice, their dosages and alternatives are listed in a table that begins on page 54. A table listing the adverse effects of some of these antimicrobials begins on page 58.

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.

Many infections can be transmitted during sexual contact. The text and tables that follow are limited to management of sexually transmitted infections (STIs) other than HIV, viral hepatitis and enteric infections. Guidelines are available from the US Centers for Disease Control and Prevention (CDC) with detailed recommendations for treatment of these diseases.

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).

Many infections can be transmitted during sexual contact. The text and tables that follow are limited to management of sexually transmitted infections (STIs) other than HIV, viral hepatitis and enteric infections. Guidelines are available from the US Centers for Disease Control and Prevention (CDC) with detailed recommendations for treatment of these diseases (MMWR Recomm Rep 2002; 51, RR-6:1). New guidelines are expected soon.

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.

Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

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.

Many infections can be transmitted during sexual contact. The text and tables [in this article] are limited to treatment of non-HIV infections associated primarily with sexual transmission.

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

(Superseded by the 2013 version. Click here to purchase.)
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 lists first-choice and alternative drugs for most parasitic infections.

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.