Products
Buspirone was available in many countries in tablet form (Buspar). It was approved in 1986 and went off the market in 2010.
Structure and properties
Buspirone (C21H31N5O2, Mr = 385.5 g/mol) is an azapirone, a piperazine and pyrimidine derivative. It is present in drugs as buspirone hydrochloride, a white crystalline powder that is soluble in water. The active metabolite 1-pyrimidinylpiperazine (1-PP) is involved in its effects.
Effects
Buspirone (ATC N05BE01) is antianxiety without muscle relaxant and anticonvulsant properties like the benzodiazepines. The effects appear to be due to interference with the dopamine and serotonin systems. The metabolite 1-PP is an alpha2 antagonist. Buspirone does not interact with GABA receptors.
Indications
Anxiety and somatic symptoms of anxiety.
Contraindications
- Hypersensitivity
- Renal insufficiency
- Liver dysfunction
- Tendency to seizures
For complete precautions, see the drug label.
Interactions
Buspirone is metabolized via CYP3A4. Concomitant administration of CYP inhibitors may increase exposure to buspirone. Full details of interactions can be found in the Drug Information Leaflet.
Adverse Effects
The most common adverse effects include dizziness, drowsiness, fatigue, headache, nervousness, agitation, drowsiness, sleep disturbances, emotional disturbances, and digestive disturbances such as nausea, dry mouth, and diarrhea. Other adverse effects are possible.
