What Is Buspar (Buspirone) Used For?
Buspar is the old brand name for buspirone, an anti-anxiety medicine of its own class that acts on serotonin receptors.
By withClaro Editorial · 2026-11-02 · 4 min read
Clinical section reviewed by Dr. Jason Tan, Consultant Psychiatrist, on October 27, 2026.
More about buspirone
Key takeaways
- Buspar (buspirone) is approved for anxiety disorders and short-term relief of anxiety symptoms.
- Buspar isn't a benzodiazepine: it showed no sign of dependence in studies and isn't a controlled substance.
- It starts at 7.5 mg twice a day, 15 mg in total, and the daily dose is split into two or three.
- It works gradually over weeks rather than calming you within minutes.
Buspar is used for anxiety. Its generic name is buspirone, an anti-anxiety medicine of a class called azapirones: not a benzodiazepine and not an SSRI. It is taken every day, and it doesn't work from the first pill. The Buspar brand is no longer sold in the US, so prescriptions are for generic buspirone. In 2024 buspirone was prescribed about 16.7 million times in the US, by ClinCalc estimates.
What is Buspar used for?
The FDA label approves buspirone for anxiety disorders and short-term relief of anxiety symptoms, and it is prescribed as a daily treatment, on its own or added to an antidepressant. Its trials were in outpatients whose diagnosis roughly matched generalized anxiety disorder, and lasted 3 to 4 weeks; longer use has not been tested in controlled trials. In two trials of 559 children and teenagers aged 6 to 17 with generalized anxiety, it did no better than placebo.
It is not approved for depression, but some prescribers add it to an antidepressant. In the 2006 STAR*D trial, 286 people whose depression had not gone into remission on citalopram had buspirone added. About 3 in 10 reached remission, similar to adding bupropion, but more stopped because of side effects, 20.6% against 12.5%.
Is Buspar a benzodiazepine?
No. The label says buspirone is not chemically or pharmacologically related to benzodiazepines, barbiturates or other sedatives. It showed no potential for abuse or dependence and is not a controlled substance. It has no cross-tolerance with benzodiazepines or other sedatives and sleeping pills, so it will not block their withdrawal: the label says to withdraw those medicines gradually before starting buspirone, especially after long use. If you take one, tell your prescriber before you start.
How does Buspar work?
Medically reviewed by Dr. Jason Tan on October 27, 2026, this section only.
It works gradually and is taken every day, not when you feel anxious. The label says its mechanism is unknown. In lab tests described in the label, it binds strongly to a type of serotonin receptor, 5-HT1A, and moderately to dopamine D2 receptors. It does not act on benzodiazepine receptors or on GABA, and it has no anti-seizure or muscle-relaxing effect and little sedation, so it doesn't calm you within minutes the way a benzodiazepine does.
It differs from SSRIs too: SSRIs block the reuptake of serotonin and are approved for depression and several anxiety disorders, while buspirone acts on serotonin receptors and is approved for anxiety only. For comparison, here is how antidepressants, which buspirone is often taken alongside, are thought to work:
Antidepressants change how the brain uses chemical messengers, but how this lifts mood is not fully understood.
Most act on serotonin, norepinephrine or both. A few, such as bupropion, also act on dopamine. Some newer treatments work differently, for example esketamine, which acts on glutamate. ## Why didn't I feel anything after taking Buspar?
Because it isn't meant to work after one pill. It is taken every day, not as needed, and the dose is raised in steps no more often than every 2 to 3 days, MedlinePlus says. Finding a dose that works can take several weeks, MedlinePlus says. More in how long Buspar takes to work.
What doses does Buspar come in?
Buspirone tablets come in 5 mg, 10 mg, 15 mg and 30 mg. The 5 mg and 10 mg tablets split only in half, while the 15 mg and 30 mg tablets split into halves or thirds. Take it the same way each day, always with food or always without, because food raises how much reaches the blood. The label starts at 7.5 mg twice a day, which is half of a 15 mg tablet, and allows up to 60 mg a day; in trials, 20 to 30 mg a day in two or three doses was common. More in Buspar dosage.
What side effects does Buspar cause?
In the trials, dizziness was the side effect with the biggest gap over placebo, 12% against 3%, along with nausea, headache and nervousness. Drowsiness was about as common as on placebo, 10% against 9%, but both the label and MedlinePlus advise against driving or using machinery until you know how it affects you. More in Buspar side effects. If you're having thoughts of harming yourself, contact emergency services or a crisis line straight away. In the US, call or text 988. In the UK, call Samaritans on 116 123. Elsewhere, find a crisis line near you.
What should you tell your prescriber before starting Buspar?
Some conditions and medicines change whether buspirone is a good fit, so name them at the first appointment. Before you start, tell your prescriber about:
- other antidepressants, and triptan migraine medicines, which raise the risk of serotonin syndrome and need closer watching at the start and after dose increases
- benzodiazepines or sleeping pills you take or are stopping
- kidney or liver problems; with severe ones, buspirone is not recommended
- how much grapefruit juice and alcohol you drink
- pregnancy, plans for pregnancy or breastfeeding
Signs of serotonin syndrome include agitation, confusion, shaking or stiff muscles, a fast heartbeat, sweating, fever, nausea and diarrhea. If they appear, call your prescriber or get urgent care.
One combination is ruled out. Buspirone must not be taken with an MAOI antidepressant or within 14 days of stopping one, in either direction, because of the risk of serotonin syndrome and high blood pressure.
Download on the App Store Buspar works gradually, so day-to-day changes are easy to miss. The withClaro app lets you log mood, sleep, energy and side effects each day, linked to your dose, and turns it into a report for your prescriber.
Related articles
Sources
- BUSPIRONE HYDROCHLORIDE tablets prescribing information, US Food and Drug Administration via DailyMed
- MedlinePlus: Buspirone
- ClinCalc DrugStats: The Top 300 Drugs of 2024
- Trivedi et al., 2006, New England Journal of Medicine: Medication augmentation after the failure of SSRIs for depression
- MotherToBaby: Buspirone
Claro articles are for self-monitoring and educational purposes only. They are not a medical device, therapist, or diagnostic tool, and do not replace care from your prescribing clinician. If you are in crisis, contact your care team, emergency services, the Samaritans (UK: 116 123), or the Crisis Text Line (US: text HOME to 741741).