Nicholas Nissen

Dr. Nicholas Nissen is a Harvard Medical School‑trained, board‑certified psychiatrist and therapist who specializes in ADHD, anxiety disorders, treatment‑resistant depression, and substance‑use issues. He earned his M.D. from Brown University's Warren Alpert Medical School and completed his psychiatry training at Harvard Medical School, where he served as Chief Resident of Student Mental Health and conducted research on non‑stimulant treatments for ADHD. Dr. Nissen also trained as a cognitive‑behavioral and exposure therapist at Boston University’s Center for Anxiety and Related Disorders and is certified in CBT through the Feeling Good Institute.

Motivated by the shortcomings of traditional behavioral health models, Dr. Nissen founded the Nissen Clinic as a concierge (Direct Primary Care) practice to provide patients with longer, more frequent visits, direct accessibility, and a holistic, patient‑centered approach. He integrates medication management, evidence‑based psychotherapies, lifestyle coaching, and innovative treatments such as ketamine‑assisted psychotherapy, TMS, and MDMA‑assisted therapy, aiming to create lasting, meaningful change for each individual.