Rapid onset of true antidepressant action.

Antidepressant medications generally are considered to have a delayed onset of action; however, recent evidence is beginning to challenge this conventional wisdom. Meta-analysis of placebo-controlled, randomized trials reveals that patients with depression are more likely to experience a clinically significant response with antidepressants than with placebo by the end of the first week of treatment. About one third of the total treatment benefit over 6 weeks is evident by the end of the first week. Early response to antidepressants is not necessarily a placebo response.