A course of therapy last between 6-12 months depending on the severity of acne and the body weight of the patient. In cases of very severe acne, such as acne involving the chest and back, a course of treatment may extend to beyond 14 months. Typically your dermatologist will start you on a very low dose to monitor for side effects and ease you into the drug. Depending on the severity of your acne you will be seen every 1-3 months to ensure your treatment is on track and that your side effects are well managed. By completing the course of medication as set by your treating dermatologist, this will ensure that you have the best possible chance of placing your acne in remission.
Dermatologist calculate your total dose by your body weight. For example, if you are 70kg, you will require 9 boxes. If you go thru one box a month, then your treatment course is 9 months. Your daily dose will depend on your side effects and the type of acne you have.