The original Hedrin product - Hedrin 4% Lotion is a medicine containing dimeticone and is available as a lotion and a spray from pharmacies nationwide. Always read the label. Contains dimeticone and cyclomethicone. Clinically proven to kill head lice with only two applications, seven days apart. Requires two applications, seven days apart. Hedrin 4% lotion is a medicine, always read the label.