- 🔬Pathophysiology
- Multifactorial — monoamine (serotonin/norepinephrine/dopamine) dysregulation, GABA/glutamate and neuroendocrine changes, genetics.
- 🩺Signs & Symptoms
- ≥2 weeks of depressed mood/anhedonia plus SIGECAPS (sleep, interest, guilt, energy, concentration, appetite, psychomotor, suicidality).
- 🎯Gold Standard Diagnosis
- Clinical (DSM-5): ≥5 of 9 symptoms for ≥2 weeks, including mood or anhedonia (PHQ-9 to screen).
- 💊First-line Treatment
- SSRIs first-line + psychotherapy (CBT); reassess if no improvement by 4 weeks.