Delayed Onset of Action of Antidepressants
Clinical Response Patterns
- The American College of Physicians, as reported in the Annals of Internal Medicine, suggests that while some improvement may begin within days, clinically significant effects of antidepressants typically require 2+ weeks, with response rates becoming similar after 4 weeks 1
- The American College of Physicians, as reported in the Annals of Internal Medicine, indicates that only about 25% of patients become symptom-free after the initial antidepressant trial, with many requiring 6-12 weeks for optimal effect, and 38% of patients do not achieve treatment response during 6-12 weeks of treatment 1
- Studies, as reported in the Annals of Internal Medicine, show that mirtazapine has demonstrated a statistically significantly faster onset of action compared to SSRIs like fluoxetine, paroxetine, and sertraline, though after 4 weeks most response rates become similar 1, 3