Can buspirone (anxiolytic medication) cause agitation?

Can Buspirone Cause Agitation?

Yes, buspirone can cause agitation as an adverse effect, particularly during the early stages of treatment or with dose increases. According to the FDA drug label, nervousness (5% vs 1% placebo) and excitement (2% vs <1% placebo) are among the commonly reported central nervous system side effects of buspirone 1.

Mechanism and Prevalence

• Buspirone works primarily through serotonergic mechanisms, acting as a partial agonist at 5-HT1A receptors, but also has effects on dopamine receptors which may contribute to agitation in some patients 2.
• In clinical trials, approximately 10% of patients discontinued buspirone due to adverse events, with 3.4% specifically citing central nervous system disturbances including nervousness and agitation 1.
• Paradoxically, buspirone is sometimes used to treat mild to moderate agitation in certain patient populations, but may take 2-4 weeks to become effective for this purpose 3.

Risk Factors and Presentation

• Agitation may be more likely to occur:

  • During the first few weeks of treatment 1
  • With dose increases 1
  • In pediatric populations (one study showed 16% of children developed increased aggression and agitation) 4
  • In patients with pre-existing psychotic disorders 5

• The agitation may manifest as:

  • Nervousness or restlessness 1
  • Excitement or activation 1
  • In rare cases, akathisia (a syndrome of restlessness) 1
  • Increased aggression in some vulnerable populations 4

Clinical Considerations

• Agitation typically appears early in treatment and may resolve with continued use as the body adjusts to the medication 1.
• The FDA drug label notes that a syndrome of restlessness has been reported in some patients shortly after initiation of treatment 1.
• In patients with psychotic disorders, buspirone may potentially worsen symptoms including agitation and paranoia 5.
• Buspirone should be started at lower doses and titrated slowly to minimize adverse effects including agitation 1.

Management of Buspirone-Induced Agitation

• If agitation occurs, consider the following approaches:
  • Reduce the dose of buspirone 1
  • Administer the medication with food to alter absorption kinetics 1
  • If severe or persistent, discontinuation may be necessary 1
  • In some cases, the agitation may resolve with continued treatment 1

Special Populations

• Elderly patients: Start with lower doses as they may be more sensitive to CNS effects 1.
• Patients with psychiatric comorbidities: Use with caution in patients with psychotic disorders as case reports suggest potential worsening of symptoms 5.
• Children: Higher risk of behavioral activation and agitation (16-24% in one study) 4.
• Patients with movement disorders: Case reports suggest buspirone may exacerbate or induce movement disorders in some patients 6.

Important Caveats

• Buspirone should not be used concomitantly with MAOIs due to risk of serotonin syndrome, which can include agitation as a symptom 1.
• Unlike benzodiazepines, buspirone does not cause withdrawal symptoms when discontinued, but it also doesn't prevent withdrawal symptoms from other sedatives 1.
• Buspirone may take 2-4 weeks to reach full therapeutic effect, and patients should be informed about potential early side effects like agitation 3.