Why Antidepressants Work for Some People—but Not Others

This video explains how antidepressants can act through at least 12 distinct brain and body mechanisms—and why simply asking “Do antidepressants work?” misses the biological and clinical heterogeneity of depression. Depression is not one illness state, and antidepressants are not one uniform treatment. In this video, consultant psychiatrist Dr Sanil Rege moves beyond the familiar “chemical imbalance” debate to explain how different treatments may influence fear circuits, emotional processing, cognition, reward, motivation, pain, inflammation, neuroplasticity and brain networks. You will learn why two people with the same diagnosis may require very different treatment approaches—and why the clinically useful question is not simply whether an antidepressant works, but: Which mechanism are we trying to introduce, for which person, in which clinical state, and at what point in time? ⏰ Timestamps / Chapters 00:00 Do antidepressants work—or is that the wrong question? 01:30 Why the “antidepressant” label is misleading 02:44 Fear, threat and anxiety-dominant depression 04:25 Emotional processing and negative bias 06:04 Cognitive dysfunction in depression 08:12 The ACE model: activity, cognition and emotion 10:01 Anhedonia, reward and motivation 12:23 Neuroplasticity: medication opens the door 13:27 Depression, chronic pain and shared circuits 14:50 Inflammation, metabolism and immune signalling 17:19 Ketamine, esketamine and rapid antidepressant effects 17:44 TMS, ECT and neuromodulation 18:22 Psychedelics, neurosteroids and hormones 19:12 Why the public antidepressant debate misses the point For clinicians, this provides a mechanism-based framework for matching treatment to the dominant functional domain rather than prescribing generically from a diagnostic label. For patients and families, it explains why antidepressants are not designed simply to “make someone happy,” why responses differ between individuals, and why medication may create an opportunity for sleep, psychotherapy, relationships, routine and behavioural change to become effective. Dr Sanil Rege, MBBS, MRCPsych, FRANZCP, is a consultant psychiatrist, founder and Academic Lead of Psych Scene, and an experienced educator who has trained more than 10,000 mental health professionals. For structured education in psychiatry, neuroscience and clinical psychopharmacology, explore The Academy by Psych Scene: https://www.academy.psychscene.com/ This video is for education only and does not provide individual medical advice. Do not start, stop or change antidepressant medication without consulting an appropriately qualified healthcare professional. #Antidepressants #Depression #MentalHealth #Psychiatry #Neuroscience #Psychopharmacology Related Videos: Not All SSRIs Are the Same-How to Pick the Right One:    • Not All SSRIs Are the Same-How to Pick the...   Your Brain Doesn’t Care If You’re Happy – Your Brain Wants THIS Instead    • Your Brain Doesn’t Care If You’re Happy – ...   🎓RESOURCES BY PSYCH SCENE: 🌐The Academy by Psych Scene: PSYCHIATRY EDUCATION REDEFINED https://academy.psychscene.com/ Revolutionary psychiatry learning. 🌐Psych Scene Hub: PSYCHIATRY TEXTBOOK OF THE FUTURE https://psychscenehub.com/ The Hub is devoted to making you a better mental health professional. Our team of academic and clinical experts bring you powerful summaries, videos and interviews in psychiatry and neurosciences. 🌐Psych Interview Online: REAL WORLD SKILLS FOR REAL WORLD SUCCESS https://www.psychinterview.com/ The Psych Interview online courses offer high-quality training to help you improve your psychiatric interview skills through self-study. 🌐Psych Scene Online: THE ONLINE COURSES TO HELP YOU SUCCEED https://ranzcpexams.psychscene.com/ Learn at your own pace with the RANZCP Written Exam prep online courses. 🌐Psych Scene: THE PSYCHIATRY TRAINING EXPERTS https://psychscene.com/ Psych Scene offers specialised training and professional development for Psychiatry Trainees, Psychiatrists, General Practitioners and Mental Health Practitioners. -- 📱SOCIALS Subscribe for weekly videos on Psychiatry and Neuroscience: Facebook:   / psychscenehub   Instagram:   / psychiatry.excellence   – 👋 LET’S CONNECT! Follow Sanil Rege on LinkedIn:   / sanilrege