How fast are antidepressants?

Background: For years, investigators have tried to determine the speed of o nset of antidepressant drugs. Claims that particular drugs may produce a fa ster response in patients than other agents have been made, but such claims have never been confirmed. Method: The authors reviewed reports from studies of the speed of onset of antidepressant therapies and other studies that revealed information on thi s topic. We compiled a list of factors that can affect the results of such studies and interpretations of study results. In addition, we reviewed lite rature concerned with methods of speeding up antidepressant responses. Results: No antidepressant medication currently available has been shown co nclusively to have a more rapid onset of action than any other. However, so me methods of augmentation may have the potential to speed responses. Somat ic therapies such as electroconvulsive therapy, phototherapy, and therapeut ic sleep deprivation may be the fastest options available at this time. Conclusion: All available antidepressant medications are usually taken for several weeks before future responders will display a significant therapeut ic benefit. If a patient does not show at least a 20% improvement within th e first 2 to 4 weeks of treatment, the treatment regimen should be altered. For patients who do show early benefits from a medication trial, one can e xpect additional benefits to accrue over an 8- to 12-week period and to imp rove overall outcome compared with those slower to respond. Future trials n eed to address methodological confounds, but a truly "faster antidepressant " will probably require new neuroscience technology.