DRUGS USED TO TREAT SCABIES AND LICE
Pyrethrins are naturally occurring pesticides derived from chrysanthemum plants. They are active against many insects and mites. Over-the-counter liquid and gel preparations of pyrethrins with piperonyl butoxide are available for the treatment of pediculosis (piperonyl bu-toxide inhibits the hydrolytic enzymes that metabolize the pyrethrins in the arthropod). A synthetic pyre-throid, permethrin (Elimite), is available by prescrip-tion. A lower concentration of permethrin (Nix) is available without prescription. Pyrethrins and perme-thrin are quite safe.