What is major depressive disorder?

Major depressive disorder is a clinical psychiatric diagnosis, not a temporary emotional state. It occurs when a person experiences a persistent and pervasive low mood or loss of interest in activities, combined with other symptoms that together last at least two consecutive weeks. The condition goes beyond sadness or grief, interfering significantly with work, relationships, sleep, appetite, concentration, and physical health.

The core diagnostic criteria include depressed mood or anhedonia (inability to feel pleasure), alongside at least five additional symptoms. These may include fatigue, feelings of worthlessness, difficulty concentrating, sleep disturbances, changes in appetite or weight, psychomotor changes (agitation or slowness), or recurrent thoughts of death. The presence and severity of symptoms determine the episode's classification and treatment approach.

This disorder differs fundamentally from normal sadness or temporary grief. Ordinary sadness responds to life events and diminishes over time. Major depressive disorder persists despite circumstance, often without an obvious trigger, and can recur throughout a person's lifetime. Early recognition and consultation with a psychiatrist is important for accurate diagnosis and appropriate treatment, which may include psychotherapy, medication, or both.