Algorithm for managing limited improvement with a first-line antidepressant. 1) Initial improvement (defined as ≥20% reduction in symptom score) to a firstline
antidepressant should be apparent within 1–4 weeks of achieving a therapeutic dose. If there is not at least an initial improvement within this time frame, and the
drug is well tolerated, the dose should be increased. If there is still limited improvement, there should be a reassessment of diagnosis (especially comorbidity), degree
of improvement (such as number and type of residual symptoms), adherence and tolerability.