Scabies oral treatment of choice:

Ans. (c) IvermectinRef. KDT 6th ed. 864* Scabies is caused by an ectoparasite sarcoptes scabei. It is highly contagious. The mite burrows through the epidermis, laying eggs which form papules that itch intensely.* Most common site of entry- finger webs.* Drugs used are:# Permethrin: broad spectrum and potent insecticide, currently most efficacious. It is DOC for scabies. MOA: It causes neurological paralysis in insects by delaying depolarization. Single application needed in most cases. Very less toxicity; 100% cure rate.# Lindane: another broad spectrum insecticide. Efficacy lower than permethrin. MOA: kills lice and mites by penetrating through their chitinous cover and affecting the nervous system.# Benzyl benzoate: oily liquid with a faint aromatic smell. It is applied over face and neck after a bath. A second coat is applied next day which is washed after 24 hours.# Crotamiton# Sulfur# Ivermectin: highly effective in scabies and pediculosis as well. It is the only ORALLY administered drug which is used for scabies (ectoparasitosis) A single dose of 0.2 mg/kg has cured almost 90- 100% of population. It is contraindicated in children < 5 yrs, pregnant and lactating women.