Some specially trained psychologists can also prescribe medications.
Medications are generally mandatory for the treatment of disorders such as schizophrenia and mania.
For other disorders such as depression, PTSD, anxiety, or obsessive-compulsive disorder, medications can be a helpful adjunct to psychotherapy. If you have been prescribed psychiatric medications, some, or all, of the following topics may be of interest to you. Unfortunately, modern medical science has not reached such a level of sophistication that a drug can be directed to exactly the aspect of brain functioning responsible for any particular symptom. Consequently, psychiatric medications saturate the brain with specific chemicals that somehow manage to get some symptom relief. I'm sorry if that seems vague, but that's the way it is.