What are the side effects of accutane? And what does the medicine do to stop acne?

Big drug! The most concerning side effect is the potential for causing severe birth defects so you have to be on birth control to use it. It can effect the liver, can make the skin more sensitive to sun, and can thin hair. It is a powerful drug similar to vitamin a that works on acne by decreasing the oil your body produces. Physicians have to take a course to prescribe it.
Dry skin. Accutane has a drying effect so dry skin/chapped lips are the more noticeable side effects. There are potential links to inflammatory bowel disease like crohn's. The major concern is pregnancy. It causes severe birth defects and extreme precaution must be used to not get pregnant while on this medicine. This can not be stressed enough. It is, however, quite effective at treating severe acne.