What is the efficacy of Buspar (buspirone) for treating generalized anxiety disorder (GAD)?

From the Guidelines

Buspirone (Buspar) is moderately effective for treating generalized anxiety disorder (GAD), with a recommended initial dosage of 5 mg twice daily, which can be gradually increased to 20 mg three times daily, as stated in the guidelines 1. The efficacy of buspirone for GAD is supported by its ability to affect serotonin and dopamine receptors in the brain, particularly the 5-HT1A receptors, which helps regulate anxiety without causing sedation or dependence. Some key points to consider when using buspirone for GAD include:

• It may take 2-4 weeks to reach full effectiveness, so patients should continue treatment even if they don't notice immediate benefits 1.
• Buspirone has a favorable side effect profile compared to other anxiety medications, with minimal risk of dependence, withdrawal, or cognitive impairment.
• Common side effects include dizziness, headache, nausea, and nervousness, which are usually mild.
• Buspirone is particularly useful for patients with a history of substance abuse, older adults, or those who need to avoid sedation.
• It can be used long-term without developing tolerance, making it appropriate for the chronic nature of GAD. Additionally, a study from 2016 found that augmenting with bupropion decreases depression severity more than augmentation with buspirone, although the evidence is low-quality 1. However, the most recent and highest quality study relevant to the question of buspirone's efficacy for GAD is not directly provided, but based on the available evidence, buspirone is a viable treatment option for GAD, especially for patients who cannot tolerate or have contraindications to other anxiety medications.

From the FDA Drug Label

The efficacy of buspirone hydrochloride tablets has been demonstrated in controlled clinical trials of outpatients whose diagnosis roughly corresponds to Generalized Anxiety Disorder (GAD). Many of the patients enrolled in these studies also had coexisting depressive symptoms and buspirone hydrochloride tablets relieved anxiety in the presence of these coexisting depressive symptoms

The efficacy of Buspar (buspirone) for treating Generalized Anxiety Disorder (GAD) has been demonstrated in controlled clinical trials.

• Key points:
  • Buspirone has been shown to be effective in relieving anxiety symptoms in patients with GAD.
  • The drug has also been effective in patients with coexisting depressive symptoms.
  • However, the effectiveness of buspirone in long-term use (more than 3 to 4 weeks) has not been demonstrated in controlled trials 2.

From the Research

Efficacy of Buspar for Treating Generalized Anxiety Disorder (GAD)

• Buspirone (Buspar) has been shown to significantly reduce symptoms of GAD, with a efficacy comparable to benzodiazepines 3, 4.
• Studies have demonstrated that buspirone is effective in treating GAD, with significant reductions in mean Hamilton Rating Scale for Anxiety (HAM-A) total scores and improvement on Clinical Global Impression measures 5.
• Buspirone has been found to be well-tolerated, with a low incidence of side effects, and is not associated with physical dependence, withdrawal, or sedation 3, 6, 4.
• The medication has also been shown to be effective in treating GAD in specific populations, such as individuals with Williams syndrome, with a sustained response and minimal side effects 7.

Comparison to Other Treatments

• Buspirone has been compared to other treatments for GAD, including benzodiazepines and antidepressants, and has been found to have a more favorable side effect profile 3, 6.
• The medication has been shown to be as effective as benzodiazepines, but with less risk of dependence and withdrawal 3, 4.
• Buspirone has also been found to be effective in combination with other treatments, such as psychotherapy, for patients who do not respond to a single treatment approach alone 3.

Dosage and Administration

• Buspirone has been studied in various dosing regimens, including twice a day (BID) and three times a day (TID), with no significant differences in efficacy or safety detected between the two treatment groups 5.
• The medication is typically started at a low dose and titrated up to a maximum dose of 30 mg/d, with a mean elimination half-life of 2.1 hours 4.