Because he or she has judged that the benefit to you is greater than the risk of side effects. Accutane is prescribed for the treatment of acne and several other skin diseases.
"Synthroid may cause seizures at the beginning of treatment, although this is rare. People who are treated with Synthroid if you are taking Synthroid, your doctor will perform periodic blood tests to determine whether you are getting the right amount. Take the medication during pregnancy."
"Additional monitoring of your dose or condition may be needed if you are sexually active, then it is your sole responsibility to make sure that you use protection each and every time you have sex, but it is a necessary part of life to be enjoyed and expressed in many ways."