Lindane Shampoo, USP 1%, is an ectoparasiticide and ovicide effective against Pediculosis humanis capitis (head lice), Pthirus pubis(crab lice), and their ova. In addition to the active ingredient, lindane, it contains triethanolamine lauryl sulfate, polysorbate 60, hydrochloric acid, acetone and purified water to form a shampoo base. The pH may be adjusted with 10% hydrochloric acid solution and/or 10% sodium hydroxide solution. Lindane is the gamma isomer of 1,2,3,4,5,6 hexachlorocyclohexane having the following structural formula: