From the Guidelines
Buspirone (Buspar) should not be taken as needed, but rather as a regularly scheduled medication, typically 2-3 times per day, to achieve its therapeutic effects. According to the guidelines for managing behavior and mood disorders 1, buspirone is most effective when taken consistently, with an initial dosage of 5 mg twice daily and a maximum of 20 mg three times daily. Unlike benzodiazepines, buspirone does not work immediately and requires 2-4 weeks of continuous use to become effective. The medication's mechanism of action involves affecting serotonin and dopamine receptors in the brain, which gradually modifies neurotransmitter activity to reduce anxiety symptoms over time. If buspirone is taken irregularly or as needed, its benefits will not be realized. Some key points to consider when taking buspirone include:
- Starting with a low dose and gradually increasing as needed and under medical supervision
- Taking the medication at the same time every day to maintain consistent levels in the system
- Being patient, as it may take several weeks to notice the full effects of the medication
- Discussing alternative options with a healthcare provider if an as-needed medication for anxiety is desired, as buspirone's pharmacodynamics make it less suitable for intermittent use.
From the FDA Drug Label
The recommended initial dose is 15 mg daily (7.5 mg b.i.d.) To achieve an optimal therapeutic response, at intervals of 2 to 3 days the dosage may be increased 5 mg per day, as needed.
The FDA drug label does not answer the question.
From the Research
Buspar (Buspirone) Usage
- Buspar (buspirone) is an anxiolytic drug used to treat generalized anxiety disorder [(2,3,4)].
- The typical dosage of buspirone is 15 mg/day, and it can be taken as needed, but it is essential to follow the prescribed dosage and administration guidelines 5.
- Buspirone has a slower onset of action compared to benzodiazepines, but it has a better safety profile and lacks dependency-producing aspects [(2,4)].
Pharmacokinetics and Pharmacodynamics
- Buspirone is rapidly absorbed after oral administration, with a mean peak plasma concentration of approximately 2.5 micrograms/L, and a time to reach the peak of under 1 hour 5.
- The absolute bioavailability of buspirone is approximately 4%, and it is extensively metabolized, with one of the major metabolites being 1-pyrimidinylpiperazine (1-PP) 5.
- Buspirone has a volume of distribution of 5.3 L/kg, a systemic clearance of about 1.7 L/h/kg, and an elimination half-life of about 2.5 hours 5.
Long-term Use and Safety
- Long-term use of buspirone for up to one year has been associated with no new or unexpected side effects, and most patients can be successfully managed on daily doses ranging from 15 to 30 mg/day 6.
- When buspirone therapy is abruptly discontinued after more than six months of therapy, there is no evidence of a withdrawal syndrome or unusual events 6.
- However, it is recommended to reevaluate the need for drug therapy periodically when using an anxiolytic agent for several months or longer to treat chronic anxiety 6.