What are the side effects of Buspar (Buspirone)?

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From the Guidelines

Buspar (buspirone) can cause several side effects, including dizziness, headache, nervousness, lightheadedness, nausea, and insomnia, with most side effects appearing early in treatment and often diminishing over time as the body adjusts to the medication.

Common Side Effects

  • Dizziness
  • Headache
  • Nervousness
  • Lightheadedness
  • Nausea
  • Insomnia Some patients may also experience drowsiness, fatigue, or difficulty concentrating.

Less Common Side Effects

  • Dry mouth
  • Blurred vision
  • Diarrhea
  • Constipation It's worth noting that Buspar can cause serotonin syndrome, especially when combined with other serotonergic medications, although this is rare 1.

Rare but Serious Side Effects

  • Serotonin syndrome, presenting with confusion, rapid heart rate, dilated pupils, muscle rigidity, and high fever Unlike benzodiazepines, Buspar doesn't cause physical dependence or withdrawal symptoms and has minimal impact on cognitive function. The standard starting dose is 5mg twice daily, which may be gradually increased to 20mg three times daily in divided doses, as indicated in the treatment guidelines 1. If you experience troublesome side effects, contact your healthcare provider before stopping the medication, as they may recommend adjusting the dosage or taking it with food to reduce stomach upset.

From the FDA Drug Label

ADVERSE REACTIONS (See also PRECAUTIONS) Commonly Observed The more commonly observed untoward events associated with the use of buspirone hydrochloride tablets not seen at an equivalent incidence among placebo-treated patients include dizziness, nausea, headache, nervousness, lightheadedness, and excitement The table that follows enumerates adverse events that occurred at a frequency of 1% or more among buspirone hydrochloride patients who participated in 4-week, controlled trials comparing buspirone hydrochloride tablets with placebo TREATMENT-EMERGENT ADVERSE EXPERIENCE INCIDENCE IN PLACEBO-CONTROLLED CLINICAL TRIALS* (Percent of Patients Reporting) Adverse ExperienceBuspirone hydrochloride (n = 477)Placebo (n = 464)

  • Incidence less than 1%. * Events reported by at least 1% of buspirone hydrochloride patients are included Cardiovascular Tachycardia/Palpitations1 CNS Dizziness12 Drowsiness10 Nervousness5 Insomnia3 Lightheadedness3
  • Decreased concentration2 Excitement2
  • Anger/Hostility2
  • Confusion2
  • Depression2 EENT Blurred vision2 Gastrointestinal Nausea8 Dry mouth3 Abdominal/gastric distress2 Diarrhea2 Constipation1 Vomiting1 Musculoskeletal Musculoskeletal aches/pains1 Neurological Numbness2 Paresthesia1 Incoordination1 Tremor1 Skin Skin rash1 Miscellaneous Headache6 Fatigue4 Weakness2 Sweating/Clamminess1

The side effects of Buspar (Buspirone) include:

  • Common side effects:
    • Dizziness
    • Nausea
    • Headache
    • Nervousness
    • Lightheadedness
    • Excitement
  • Cardiovascular side effects:
    • Tachycardia/Palpitations
  • CNS side effects:
    • Drowsiness
    • Insomnia
    • Decreased concentration
    • Anger/Hostility
    • Confusion
    • Depression
  • Gastrointestinal side effects:
    • Dry mouth
    • Abdominal/gastric distress
    • Diarrhea
    • Constipation
    • Vomiting
  • Musculoskeletal side effects:
    • Musculoskeletal aches/pains
  • Neurological side effects:
    • Numbness
    • Paresthesia
    • Incoordination
    • Tremor
  • Skin side effects:
    • Skin rash
  • Miscellaneous side effects:
    • Headache
    • Fatigue
    • Weakness
    • Sweating/Clamminess 2

From the Research

Side Effects of Buspar (Buspirone)

  • The most frequently reported adverse events for buspirone include dizziness, headache, and nausea 3
  • Other common side effects consist of CNS effects, such as dizziness and light-headedness, and gastrointestinal effects, including nausea 4
  • Buspirone may cause palpitations, with a significantly greater incidence in patients receiving buspirone 15 mg twice daily compared to 10 mg three times daily 3
  • There is a risk of persistent movement disorders, including dyskinesia, dystonia, and tremors, associated with the use of buspirone 5
  • Serotonin syndrome, a potentially lethal condition, may develop when buspirone is administered with other serotonergic drugs, such as fluoxetine 6
  • Long-term administration of buspirone may produce similar effects to classical anxiolytics, such as chlordiazepoxide, on behavioral tests of anxiolytic action 7

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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