Posted by SLS on June 3, 2006, at 8:04:55
In reply to What really is a fair antidepressant trial period?, posted by nickguy on June 2, 2006, at 23:27:23
> They say 6 weeks for these things to reach their full potential, but if you don't notice anything at all before that six weeks, is it fair to say that it's not effecting you and is probably not going to? I mean, after three weeks, if this is the right med for you you'll probably notice some positive changes, am I wrong?
The percentage of eventual responders declines significantly if one does not see any results after three weeks at a therapeutic dosage. However, I think there are enough people who take 6 weeks to respond such that it still makes sense to complete a 6 week trial. One problem with evaluating drugs at the three week mark is that the improvements are often too subtle for the patient to recognize. An evaluation using a depression rating scale would probably help with this recognition. With Prozac (fluoxetine), you might have to add another two weeks because of the added time it takes to attain therapeutic levels.I think the bottom line is that if you have failed multiple drug trials and have fewer options remaining, it becomes more critical to give drugs adequate time to work.
- ScottAm J Psychiatry. 2000 Sep;157(9):1423-8. Related Articles, Links
Click here to read
Timing of onset of antidepressant response with fluoxetine treatment.Nierenberg AA, Farabaugh AH, Alpert JE, Gordon J, Worthington JJ, Rosenbaum JF, Fava M.
Depression and Clinical Research Program, Massachusetts General Hospital, Boston, MA 02114, USA. anierenberg@partners.org
OBJECTIVE: The purpose of this study was to assess the time until onset of antidepressant response with fluoxetine treatment. METHOD: The authors evaluated 182 outpatients with major depression who had a sustained acute response to fluoxetine treatment. The outpatients received 8 weeks of treatment with 20 mg/day of fluoxetine and were assessed biweekly with the 17-item Hamilton Depression Rating Scale. The onset of response was defined as a 30% decrease in score on the Hamilton depression scale that persisted and led to a 50% decrease by week 8. The Kaplan-Meier product limit and Cox regression analysis were used to model the relationship between relevant variables and time until onset of response. RESULTS: The authors found that at weeks 2, 4, and 6, the probabilities of having an onset of response (for responders) were 55.5%, 24.7%, and 9.3%, respectively. The cumulative probabilities of onset of response at each time point were 55.5%, 80.2%, and 89.5%. Neither demographics nor clinical characteristics of depression predicted time until initial response. CONCLUSIONS: These data suggest that more than half of eventual responders to fluoxetine treatment at 8 weeks start to respond by week 2; over 75% start to respond by week 4. Conversely, the lack of onset of response at 4-6 weeks was associated with about a 73%-88% chance that patients would not have an onset of response by 8 weeks.
Publication Types:
* Clinical Trial
PMID: 10964858 [PubMed - indexed for MEDLINE]
poster:SLS
thread:652177
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