Major Depressive Disorder

Major depressive disorder (MDD) is more than sadness after a difficult event. It is a syndrome of mood, cognition, physical function, and behaviour that persists long enough and severely enough to change how a person lives. The same syndrome can present as tearfulness, irritability, slowed thinking, loss of appetite, insomnia, unexplained pain, or withdrawal from usual activities. The first nursing question is not which antidepressant should be used. It is whether the person is safe, whether the presentation could be bipolar depression or another medical or substance-related condition, and how much function has been lost. A patient may deny feeling sad yet describe anhedonia, exhaustion, hopelessness, and recurrent thoughts of death. Those details can carry more clinical weight than appearance or a screening score. Treatment is judged by recovery toward remission and restored function, not merely by a small reduction in symptoms. Risk can change during treatment: agitation, impulsivity, or returning energy may appear before hope improves. That is why suicide assessment and follow-up remain active parts of care even when the patient says the medication is beginning to work.