FDA Fails to Ban Toxic Lice and Scabies Treatment

In November 2012, the Natural Resources Defense Council (NRDC) announced that the Food and Drug Administration (FDA) had denied the group’s petition to ban the dangerous insecticide lindane. The chemical, used in prescription lotions and shampoos to treat head lice and scabies, has been linked to serious side effects, including seizures, blood disorders and death. The FDA currently requires a black box warning for all lindane products to inform patients of the risk of seizure and death.

Head lice and scabies infestations are common among children, and serious cases also occur among elderly or infirm individuals living in nursing homes or other institutions. Safer, more effective alternatives to lindane for treating lice and scabies have been available for decades. Caregivers to children and those with relatives living in institutions should be aware of the risks of lindane and seek to ensure that loved ones are not exposed to this dangerous chemical.

A dangerous and ineffective treatment

Lindane is an insecticide sold as a shampoo or skin cream. Although it was once widely used for the treatment of lice and scabies, experts have increasingly recommended against its use as more information has emerged about the drug’s side effects and as safer, more effective treatment options have become available.

Lindane can be absorbed through the skin and has toxic effects on the nervous system. It can lead to side effects that range in severity from skin irritation, dizziness and headache to seizures, blood disorders (from failed blood cell production due to poisoning of the bone marrow) and death.

At least 17 deaths associated with lindane use have been reported to the FDA, along with many more cases of seizures and other serious side effects. Most cases of serious side effects or death are associated with inappropriate use, although in some cases, severe reactions were reported after apparently normal use.

The risk of side effects can increase with misuse of the product, including accidental or deliberate swallowing, applying the product more than once, applying it to too large an area or leaving it on for too long. Some of the cases of seizures or deaths occurred after lindane had been applied following a hot bath or shower, which is not recommended because such moist heat is thought to increase absorption through the skin.

Children and small (less than 110 pounds) or elderly people appear to be at higher risk of serious injury from lindane. Smaller people have a larger body-surface-to-volume ratio, which may account in part for the increase in risk of toxic exposure for children and small adults.

In addition to being dangerous, lindane also is relatively ineffective. Use of the chemical over the decades has led to widespread resistance throughout the world, making it one of the least effective products of its kind.

A recent study used lindane to treat head lice collected in Florida. In the study, lindane killed only 2 percent of lice after 20 minutes and fewer than 20 percent after three hours. Furthermore, because the product’s instructions recommend applying it for 10 minutes, these results demonstrate that appropriate use of lindane would render the product totally ineffective when used according to the instructions. An exposure of 20 minutes to three hours, as in the study, would dramatically increase the risk of toxic effects.

Lindane was less effective on the Florida lice than the much safer, over-the-counter medicines pyrethrins (A-200, PRONTO, R&C, RID, TRIPLE X) and permethrin lotion 1 percent (NIX). It also was less effective than the prescription drug malathion lotion 0.5 percent (OVIDE).

Efforts to ban lindane

The NRDC petition, specifically citing the drug’s safety risks (particularly for young children) and lack of effectiveness, was the latest in a long series of efforts by consumer groups to ban lindane for medical use.

Public Citizen was one of the first consumer groups urging the FDA to ban lindane, first in 1983 and again in 1995. The 1995 petition came after analyzing 162 reports of adverse reactions, including convulsions in 50 people and six deaths.

The Cancer Prevention Coalition also petitioned the FDA in 1995 to ban the chemical based on evidence that it caused cancer in animals along with reports of increased rates of brain cancer in children treated with lindane shampoos.

The FDA’s response to the 1995 petitions was to restrict the drug’s use to second-line therapy only (i.e., using the drug in cases in which other treatments have failed or are not tolerated).

The agency’s decision to keep lindane on the market puts it at odds with other public health agencies, both in the U.S. and abroad. In 2006, the U.S. Environmental Protection Agency canceled registrations of all pesticide products containing lindane because they can remain in the environment and cause drinking water contamination. In 2009, more than 160 nations agreed to ban lindane’s use and production under the Stockholm Convention on Persistent Organic Pollutants.

Due in part to concerns about water quality, California banned pharmaceutical use of lindane in 2002. A study following the California ban found a noticeable decrease in drinking water contamination in the state. Researchers also noted a dramatic decline in poison control center calls related to accidental exposure to lindane during the same period.

The World Health Organization recommended against using lindane for scabies or lice as early as 1993, due to its toxic effects and ability to stay in the environment after use. As of 2009, the American Academy of Pediatrics no longer recommends lindane as a treatment for lice in children.

Misleading claims

In 2007, the FDA sent a warning letter to Morton Grove Pharmaceuticals, the only U.S. manufacturer of lindane creams and shampoos, alleging that the company’s website minimized the most serious and important risk information and promoted the product inappropriately for use in children.

Morton Grove’s website on lindane, www.lindane.com, claims to tell consumers “the truth about lindane” yet fails to prominently display the FDA-required boxed warning or mention seizure risks on its main page or any of the pages in its main menu. (To read the warning, one must click one of the safety information links at the bottom of a page.)

The company also uses consumer groups’ repeated unsuccessful attempts to ban the product as a marketing point, making the prominent claim that the FDA has “[r]epeatedly . . . concluded that the health benefits of lindane medications . . . outweigh any of the potential risks.”

Safer alternative treatments

If you or a loved one need treatment for lice or scabies, avoid using lindane. Though once the only approved treatment for lice and scabies, newer, safer treatments are now widely available.

Two FDA-approved treatments for lice are available over the counter: pyrethrins and permethrin lotion 1 percent. Both are acceptable first-line options for treatment, although pyrethrins should be avoided by people with allergies to ragweed or chrysanthemums, as they may experience wheezing or skin irritation.

Use these products as directed and do not combine them with other treatments or home remedies, as that may affect how the products work. After treatment, manually check hair and use a nit comb to remove eggs and lice from wet hair every two or three days to reduce the chance of reinfestation. You also should clean combs, pillowcases and other items that have touched the person’s head during the two days before treatment. Intensive housecleaning is not necessary, as head lice survive fewer than one to two days once they fall off a person. Avoid fumigant sprays, which can be toxic.

If live lice are seen eight to 12 hours after treatment and seem just as active as before, the lice may be resistant. In this case, do not treat again. Instead, consult a doctor to obtain a prescription for an FDA-approved prescription product, such as benzyl alcohol lotion 5 percent (ULESFIA LOTION). This is a nontoxic product that kills lice by asphyxiation and is approved for children 6 months of age and older.

Another prescription product, malathion lotion 0.5 percent (OVIDE), is effective at killing lice but must be used carefully according to directions. Malathion is flammable, so hair treated with malathion should be left to air dry (rather than using a hair dryer) and must remain on hair, uncovered, for eight to 12 hours. Malathion has also not been tested in children under 6 years old and is not approved for children younger than 2 years old.

No treatment for lice is 100 percent effective at killing eggs, meaning that re-treatment is usually recommended nine days after the first successful treatment.

For scabies, two prescription medications offer safer alternatives to lindane. Permethrin cream 5 percent (ELIMITE) is approved to treat scabies in children at least 2 months of age, and crotamiton lotion or cream 10 percent (EURAX, CROTAN) are approved for adults but not children.

Apply these medications as instructed by your doctor. Do not re-treat immediately if symptoms persist, as it may take two to four weeks for itching and other symptoms to subside, even if all the mites and eggs are killed. If itching does persist beyond four weeks, or new burrows or rashes appear, a new treatment or re-treatment may be necessary.

Anyone who has had direct skin-to-skin contact with the infected person in the past month should be examined and treated for scabies as well, as it may take two to six weeks before symptoms appear. Bedding, clothing and towels used any time during the three days prior to treatment should be washed in hot water and dried in a hot dryer or sealed in a plastic bag for at least 72 hours.