Acne is one of the most common skin problems which starts around adolescence and may continue upto the thirties. The severity varies with each patient, ranging from occasional one to few to severe nodulocystic scarring type of acne. What the doctor prescribed to you is the correct medicine. Be sure that you don't scratch the acne lesion otherwise it will result in scar formation. Drink lots of water (2 -  3 liters or more), eat lots of fresh vegetables and fruits. Avoid bakery products, oily food and food with high glycaemic index.