Before Using This Medicine

If you are using this medicine without a prescription, carefully read any precautions on the label. For topical permethrin, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to permethrin; to other synthetic pyrethroids, such as those found in household insecticides; to pyrethrins or chrysanthemums; or to veterinary insecticides containing permethrin. Also tell your health care professional if you are allergic to any other substances, such as preservatives or dyes.

Pregnancy—Permethrin has not been studied in pregnant women. However, this medication has not been shown to cause birth defects or other problems in animal studies.

Breast-feeding—It is not known whether permethrin passes into the breast milk. However, animal studies have shown that permethrin can cause tumors. Be sure you have discussed the risks and benefits of the medicine with your doctor.

Children—Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of topical permethrin in children with use in other age groups.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of topical permethrin in the elderly with use in other age groups.

Other medicines—Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are using any other prescription or nonprescription (over-the-counter [OTC]) medicine that is to be applied to the hair, scalp, or skin.

Other medical problems—The presence of other medical problems may affect the use of topical permethrin. Make sure you tell your doctor if you have other medical problems, especially:

• Severe inflammation of the scalp—Use of permethrin may make the condition worse