When over-the-counter remedies fail, it could be time to get a prescription head lice treatment from your doctor. Prescription treatments can effectively kill head lice that have built up a resistance to the ingredients contained in drugstore topicals. However, prescription head lice treatments are stronger and come with more consumer warnings from the U.S. Food & Drug Administration.
Doctor's First Choice
Before writing a prescription for a head lice treatment, most doctors will first recommend an over-the-counter shampoo that contains pyrethrin or permethrin for use in those over the age of two. When used according to the directions, these products can eliminate a head lice infestation. However, there are instances when lice in certain geographic locations have grown resistant to pyrethrin and permethrin, in which case a prescription topical may be recommended.
Benzyl Alcohol Lotion
In April 2009, the FDA approved a new prescription lice treatment for children 6 months of age or older. The treatment, which goes by the trade name of Ulesfia, contains benzyl alcohol (5 percent) as its active ingredient and is the first of its kind to receive FDA approval. According to the FDA, studies conducted in 600 people infected with head lice yielded a 75 percent effectiveness rate after two 10-minute treatments. Ulesfia kills live lice, but not nits (louse eggs), so wet-combing is an important component when using this treatment. Benzyl alcohol lotion does have potential harmful side effects, including scalp, skin and eye irritation and numbness where the treatment was applied. Serious side effects, including coma and death, could result when the treatment is used in infants younger than 6 months.
Lindane is another prescription treatment that can be effective on stubborn head lice. However, lindane is considered a second-line treatment when over-the-counter treatments have failed, and the FDA has issued warnings about the hazardous side-effects of lindane when the treatment is used inappropriately. Lindane is risky for use in children and anyone weighing less than 110 pounds. Nor is it a good option for women who are pregnant or breast-feeding, or those who have HIV/AIDS or a seizure disorder. According to the FDA, three deaths have resulted when patients did not use lindane according to the drug's instructions--one death was a suicide cause by ingestion of lindane. The FDA cautions that lindane should be "prescribed carefully."
The brand name for this prescription head lice treatment is Ovide; however, in March 2009, a generic equivalent of Ovide was released which goes by the name of "malathion lotion." According to the FDA, malathion is a safer option than lindane. It too is applied to the hair and scalp similar to other prescription head lice treatments. Malathion is flammable and must be kept away from heat. In addition, pregnant and breast-feeding women should talk to their doctor about the safety of this treatment.
Is A Prescription Necessary?
A study conducted by the Harvard School of Public Health did indicate that some head lice are resistant to permethrin and and pyrethrin; however, the study results were careful to say that this should not be interpreted that all or most head lice have built up a resistance to these treatments. Before asking your doctor for a prescription head lice treatment, make sure that there are no other factors that could be causing a reinfestation. Has the home been thoroughly vacuumed and the infested person's clothing, bedding and towels been washed in hot water and dried on hot heat? Was the hair wet-combed to remove nits after treatment? If your or a child continues to exhibit head lice, it could be due to repeated exposure to someone with an untreated infestation or an environment where head lice have not been treated.