Hedrin 4 lotion spray is a liquid lotion for the eradication of head lice and eggs hedrin contains the active ingredient dimeticone which kills the head lice in a innovative way instead of using conventional insecticides hedrins active ingredient encapsulates the lice and prevents them from functioning another bonus with using dimeticone is that the lice do not build up a resistance to itif a member of the family or a friend has live head lice check all the other family members and friends