Pharmacokinetics of Malathion Gel 0.5% and Malathion 0.5% Lotion (Ovide) in Patients With Head Lice

Inclusion Criteria: * Male or non-pregnant female * Patients 18 years of age or older and healthy presenting with Pediculosis capitis * The Patient must be willing to consent to the Patient's treatment with Malathion Gel 0.5% or Ovide Lotion 0.5% and for blood drawings before and after medication administration. Exclusion Criteria: * Individuals with history of irritation or sensitivity to pediculicides or hair care products * Individuals with any visible skin/scalp condition at the treatment site which, in the opinion of the investigative personnel, or Sponsor, will interfere with the evaluation. * Individuals previously treated with a pediculicide within 4 weeks of the study. * Individuals who exhibit potential signs and symptoms of cholinesterase inhibition. * Patients currently receiving sulfonamide antibiotics or ivermectin.