Most of us refer to pdocs as someone who is

...licensed physicians (MD or DO-this is the one most people are referring to when they not pdoc) who specialize in the evaluation, diagnosis, and treatment of mental disorders. Their medical and psychiatric training prepares them to treat adults and children. Psychiatrists can prescribe medications, if needed.

By shrink - you may be referring to a therapist - so the answer is no for them presicribing anything.

or shrink - you may be reffering to The term "Psychiatrist" means a person who is legally qualified and licensed to practice psychiatry - no for prescribing anything.