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Buspimen: Full Drug Profile

Medically reviewed by Min Clinic Staff | Updated: January 2026

Buspimen - General Information

An anxiolytic agent and a serotonin receptor agonist belonging to the azaspirodecanedione class of compounds. Its structure is unrelated to those of the benzodiazepines, but it has an efficacy comparable to diazepam.

 

Pharmacology of Buspimen

Buspimen is used in the treatment of generalized anxiety where it has advantages over other antianxiety drugs because it does not cause sedation (drowsiness) and does not cause tolerance or physical dependence. Buspimen differs from typical benzodiazepine anxiolytics in that it does not exert anticonvulsant or muscle relaxant effects. It also lacks the prominent sedative effect that is associated with more typical anxiolytics. in vitro preclinical studies have shown that buspirone has a high affinity for serotonin (5-HT1A) receptors. Buspimen has no significant affinity for benzodiazepine receptors and does not affect GABA binding in vitro or in vivo when tested in preclinical models. Buspimen has moderate affinity for brain D2-dopamine receptors. Some studies do suggest that buspirone may have indirect effects on other neurotransmitter systems.

 

Buspimen for patients

Buspirone is used for the treatment of nervousness and anxiety. Optimum results are usually seen after three to four weeks of treatment. This medication may be taken with or without food. Inform your physican if you are pregnant or nursing. Buspirone may cause dizziness and drowsiness; use caution while driving or operating hazardous machinery. Do not take any other sedating drugs or drink alcohol while taking this medication. Do not take this medication with a monoamine oxidase inhibitor. Notify physician if you develop muscle spasms, uncontrolled twitching in the face and body, or uncontrolled tongue movements.

 

Buspimen Interactions

It is recommended that buspirone hydrochloride not be used concomitantly with MAO inhibitors Because the effects of concomitant administration of buspirone HCl with most other psychotropic drugs have not been studied, the concomitant use of buspirone HCl with other CNS-Active drugs should be approached with caution.

There is one report suggesting that the concomitant use of trazodone hydrochloride (Desyrel) and buspirone HCl may have caused 3- to 6-fold elevations on SGPT (ALT) in a few patients. In a similar study, attempting to replicate this finding, no interactive effect on hepatic transaminases was identified.

In a study in normal volunteers, concomitant administration of buspirone HCl and haloperidol resulted in increased serum haloperidol concentrations. The clinical significance of this finding is not clear.

In vitro, buspirone does not displace tightly bound drugs like phenytoin, propranolol, and warfarin from serum proteins. However, there has been one report of prolonged prothrombin time when buspirone was added to the regimen of a patient treated with warfarin. The patient was also chronically receiving phenytoin, phenobarbital, digoxin, and levothyroxine sodium. In vitro, buspirone may displace less firmly bound drugs like digoxin. The clinical significance of this property is unknown.

 

Buspimen Contraindications

Buspirone HCl is contraindicated in patients hypersensitive to buspirone hydrochloride.

 

Additional information about Buspimen

Buspimen Indication

For the management of anxiety disorders or the short-term relief of the symptoms of anxiety, and also as an augmention of SSRI-treatment against depression.

Mechanism Of Action
Buspimen binds to 5-HT type 1A serotonin receptors on presynaptic neurons in the dorsal raphe and on postsynaptic neurons in the hippocampus, thus inhibiting the firing rate of 5-HT-containing neurons in the dorsal raphe. Buspimen also binds at dopamine type 2 (DA2) receptors, blocking presynaptic dopamine receptors. Buspimen increases firing in the locus ceruleus, an area of brain where norepinephrine cell bodies are found in high concentration. The net result of buspirone actions is that serotonergic activity is suppressed while noradrenergic and dopaminergic cell firing is enhanced.
Drug Interactions
Clarithromycin Clarithromycin increases the effect and toxicity of buspirone
Food Interactions
Avoid alcohol.
Generic Name
Buspirone
Synonyms
Buspirona [INN-Spanish]; Buspirone HCL; Buspironum [INN-Latin]
Drug Category
Anti-anxiety Agents; Serotonin Agonists; Anxiolytics sedatives and hypnotics
Drug Type
Small Molecule; Approved
Other Brand Names containing Buspirone
Ansial; Ansiced; Anxiron; Axoren; Bespar; Buspar; Buspimen; Buspinol; Buspisal; Censpar; Lucelan; Narol; Travin;
Absorption
Rapidly absorbed in man. Bioavailability is low and variable (approximately 5%) due to extensive first pass metabolism.
Toxicity (Overdose)
Oral, rat LD50 = 136 mg/kg. Symptoms of overdose include dizziness, drowsiness, nausea or vomiting, severe stomach upset, and unusually small pupils.
Protein Binding
95% (approximately 70% bound to albumin, 30% bound to alpha 1 -acid glycoprotein)
Biotransformation
Metabolized hepatically, primarily by oxidation by cytochrome P450 3A4 producing several hydroxylated derivatives and a pharmacologically active metabolite, 1-pyrimidinylpiperazine (1-PP)
Half Life
2-3 hours (although the action of a single dose is much longer than the short halflife indicates).
Dosage Forms of Buspimen
Tablet Oral
Chemical IUPAC Name
8-[4-(4-pyrimidin-2-ylpiperazin-1-yl)butyl]-8-azaspiro[4.5]decane-7,9-dione
Chemical Formula
C21H31N5O2
Organisms Affected
Humans and other mammals