If acne is a possible side effect, ask if you can take a different medicine. You may not see the benefit of this treatment for a few months, so using other acne medications with it the first few weeks may help. Why it happens and what you can do for it Acne can be particularly frustrating for adults. In one study of girls ages 9 to 10, Treatment of acne skin find adult percent of them had acne lesions. It may take a few weeks before you see any improvement.