Both are available as lotions, which are applied in a thin film over the entire body from the scalp to the soles of the feet, left on 8 to 12 hours overnight, and then washed off. A single treatment is usually effective. Itching may persist for a couple of weeks after treatment since the dead mites persist in the skin until absorbed. Therefore you shouldn't consider the treatment to have been ineffective unless new spots erupt after two weeks. If your scalp is itchy, and you see tiny bugs walking around in your hair and very small white spots, or nits, glued to your hair shafts, then you have lice, the most common scalp and hair insect infestation.
Treatment is also with a lindane shampoo.
Retreatment is usually not necessary although occasionally some of the eggs, the nits, may escape. If after a week, you still see live insects, you'll have to shampoo with lindane again. You can also remove the nits with a special fine nit comb. This is one doctor who makes housecalls. People with lupus often find themselves in chronicpain, but there are ways to find relief.