Buspar has some of the highest level evidence for augmentation of SSRI's for MDD. Please read STAR*D, where Buspar performed as well as all the other augmentation strategies.
http://www.nimh.nih.gov/trials/practical/stard/allmedicationlevels.shtml
"A. For the first time, doctors and people with depression now have extensive data on antidepressant treatments from a federally funded, large-scale, long-term study directly comparing treatment strategies.
Results from level 2 indicate that if a first treatment with one SSRI fails, about one in four people who choose to switch to another medication will get better, regardless of whether the second medication is another SSRI or a medication of a different class. And if patients choose to add a new medication to the existing SSRI, about one in three people will get better. It appears to make some—but not much—difference if the second medication is an antidepressant from a different class(e.g. bupropion) or if it is a medication that is meant to enhance the SSRI (e.g. buspirone). Because the switch group and the add-on group cannot be directly compared to each other, it is not known whether patients are more likely to get better by switching medications or by adding another medication."
The problem with Buspar is that people don't get it up to a high enough dose before they give up on it.
Aside from SSRI augmentation, I have found Buspar to be helpful for geriatric anxiety where you want to avoid using a benzo. Even if it's just placebo response - that's pretty good sometimes!
Here's a cochrane review as well: Azapirones for generalized anxiety disorder
Chessick CA, Allen MH, Thase ME., Batista Miralha da Cunha AABC, Kapczinski FFK, Silva de Lima M, dos Santos Souza JJSS
Azapirones for generalized anxiety disorder (GAD)
Generalized anxiety disorder is one of the most common anxiety disorders and can be costly if unrecognized or left untreated. Azapirones are a group of drugs that work at the 5-HT1A receptor and are used to treat patients suffering from GAD. This systematic review evaluates the effectiveness of azapirones compared to other treatments. From the results of 36 randomized controlled trials, azapirones appear to be superior to placebo in short-term studies (four to nine weeks) but may not be superior to benzodiazepines. We were unable to conclude if azapirones were superior to antidepressants, psychotherapy or kava kava. As GAD is generally chronic in nature, conclusions about azapirones' long-term efficacy are not able to be made and longer term trials are needed.
This is a Cochrane review abstract and plain language summary, prepared and maintained by The Cochrane Collaboration, currently published in The Cochrane Database of Systematic Reviews 2011 Issue 8, Copyright © 2011 The Cochrane Collaboration. Published by John Wiley and Sons, Ltd.. The full text of the review is available in The Cochrane Library (ISSN 1464-780X).
This record should be cited as: Chessick CA, Allen MH, Thase ME., Batista Miralha da Cunha AABC, Kapczinski FFK, Silva de Lima M, dos Santos Souza JJSS. Azapirones for generalized anxiety disorder. Cochrane Database of Systematic Reviews 2006, Issue 3. Art. No.: CD006115. DOI: 10.1002/14651858.CD006115
Editorial Group: Depression, Anxiety and Neurosis Group
This version first published online: July 19. 2006
Last assessed as up-to-date: May 23. 2006
Abstract
Background
Azapirones are a group of drugs that work at the 5-HT1A receptor and are used to treat patients suffering from generalized anxiety disorder (GAD). However, several studies have shown conflicting results. Whether azapirones are useful as first line treatment in general anxiety disorders still needs to be answered.
Objectives
To assess the efficacy and the acceptability of azapirones for the treatment of GAD.
Search strategy
Initiallyt the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR) and The Cochrane Central Register of Controlled Trials (CENTRAL) were searched, incorporating results of group searches of MEDLINE (1966 to June 2005), EMBASE (1980 to June 2005), CINAHL (1982 to June 2005), PsycLIT (1974 to June 2005), PSYNDEX (1977 to June 2005), and LILACS (1982 to June 2005). Subsequently the revised Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Registers (CCDANCTR-Studies and CCDANCTR-References) were searched on 21-10-2005. Reference lists of relevant papers and major text books of anxiety disorder were examined. Authors, other experts in the field and pharmaceutical companies were contacted for knowledge of suitable trials, published or unpublished. Specialist journals concerning azapirones were handsearched.
Selection criteria
Randomized controlled trials of azapirones, including buspirone versus placebo and/or other medication and/or psychological treatment, were included. Participants were males and females of all ages with a diagnosis of generalized anxiety disorder.
Data collection and analysis
Data were extracted from the original reports independently by CC, MA and MT. The main outcomes studied were related to the objectives stated above. Data were analysed for generalized anxiety disorder versus placebo, versus other medication and versus psychological treatment separately. Data were analysed using Review Manager Version 4.2.7.
Main results
Thirty six trials were included in the review, reporting on 5908 participants randomly allocated to azapirones and/or placebo, benzodiazepines, antidepressants, psychotherapy or kava kava. Azapirones, including buspirone, were superior to placebo in treating GAD. The calculated number needed to treat for azapirones using the Clinical Global Impression scale was 4.4 (95% confidence interval (CI) 2.16 to 15.4). Azapirones may be less effective than benzodiazepines and we were unable to conclude if azapirones were superior to antidepressants, kava kava or psychotherapy. Azapirones appeared to be well tolerated. Fewer participants stopped taking benzodiazepines compared to azapirones. The length of studies ranged from four to nine weeks, with one study lasting 14 weeks.
Authors' conclusions
Azapirones appeared to be useful in the treatment of GAD, particularly for those participants who had not been on a benzodiazepine. Azapirones may not be superior to benzodiazepines and do not appear as acceptable as benzodiazepines. Side effects appeared mild and non serious in the azapirone treated group. Longer term studies are needed to show that azapirones are effective in treating GAD, which is a chronic long-term illness.
