A randomized, single-dose, parallel group, comparative PK study. Patients will be randomly assigned in 1:1 ratio to the study products. Twenty four (24) consenting patients, age 18 years and older, who meet Inclusion/Exclusion criteria will be enrolled in this study. 12 Patients will be treated with Malathion Gel, 0.5% and other 12 Patients will be treated with Ovide Lotion 0.5%. The study will be single centre and conducted only in India. The primary objective of this study is to compare the systemic exposure of Malathion 0.5% Gel manufactured by Taro Pharmaceuticals USA, Inc. to that of the OVIDE Lotion 0.5%, currently marketed by Taro Pharmaceutical USA, Inc., in adult Patients with head lice. The secondary objective is to determine the link between the exposure and cholinesterase activity.
In this study, 24 adult patients with head lice will be treated with a topical malathion head lice treatment; 12 patients will be treated with a novel product, Malathion Gel, 0.5%, and other 12 patients will be treated with Ovide Lotion 0.5% marketed by Taro Pharmaceuticals USA, Inc. The primary objective of this study is to compare the blood level exposure of Malathion 0.5% Gel to that of the OVIDE Lotion 0.5%.