PMHNPs provide comprehensive psychiatric services, including evaluation, diagnosis, treatment planning, medication management, and psychotherapy for patients with mental health disorders such as depression, anxiety, bipolar disorder, schizophrenia, PTSD, and substance use disorders. A Psychiatric Mental Health Nurse Practitioner (PMHNP) is an advanced practice registered nurse (APRN) with a master's (MSN) or doctoral (DNP) degree specializing in mental health care.