Benzoyl peroxide is an antibacterial ingredient, and it’s very effective at killing the P. acnes bacteria that causes breakouts. But benzoyl isn’t without its downsides. The leave-on creams and cleansing treatments can dry out sensitive skin and bleach clothing if you aren’t careful. Board-certified dermatologist Eric Meinhardt, M.D., previously told SELF that it's best to stick to formulations that have no more than 2 percent of benzoyl peroxide listed on the active ingredients chart; stronger concentrations are harder on your skin without being any tougher on bacteria.
Stronger cases may call for prescription retinoids (such as Retin-A or Tazorac), which “are really the standard of care for most acne therapy,” says Joshua Zeichner, MD, director of cosmetic and clinical research in dermatology at Mount Sinai Hospital in New York City. Certain drugs, such as Epiduo and Ziana, combine retinoids with antibacterials and may be more effective than separate products. Because retinoids also have anti-wrinkle properties (they help stimulate collagen production), they are especially beneficial for adult acne sufferers.
Acne medications work by reducing oil production, speeding up skin cell turnover, fighting bacterial infection or reducing inflammation — which helps prevent scarring. With most prescription acne drugs, you may not see results for four to eight weeks, and your skin may get worse before it gets better. It can take many months or years for your acne to clear up completely.