Absorption of gamma benzene hexachloride following application of Kwell shampoo

Serum concentrations of gamma benzene hexachloride were determined in 9 children following application of 1% GBH shampoo for treatment of pediculosis capitis. GBH was present in the blood of all patients 2-24 hours following application. Four patients, who were retreated because of the persistence of living lice, had GBH in their pretreatment blood specimens. GBH levels in these latter patients were larger after retreatment than after the initial application, indicating that there may have been accumulation of the drug.