If there is a genuine medical need for a drug then you have to weigh the benefit of a drug vs. the risk. Addiction is obviously a risk but obviously there are benefits (ie being off street drugs). Is he under the care of an addiction doctor? Suboxone is used to wean people off opiates. Xanax is for controlling anxiety. Both are addictive and dosage needs to be monitored closely and he has to adhere to the instructions of the doctor.