When acne gets severe, it can cause painful nodules and cysts in the skin and can lead to lifelong pitting and scarring. The key is to start treatment before the damage is done.
Some patients are sensitive or even allergic to it, however.
Retin-A also unclogs pores by a peeling of the face, and can be very effective against acne. Retin-A must be applied only at night and washed off in the morning, since it sensitizes the skin to the sun. Although some patients can't tolerate Retin-A either, many show a significant improvement at 4 to 6 weeks, with optimal benefits at 3 months. Tetracycline or erythromycin are often used orally for acne. Tetracycline can make the birth control pill less effective, as well as cause birth defects.