• Molecular NameBuspirone
  • SynonymBuspirona [INN-Spanish]; Buspirone; Buspirone HCL; Buspironum [INN-Latin]
  • Weight385.512
  • Drugbank_IDDB00490
  • ACS_NO36505-84-7
  • Show 3D model
  • LogP (experiment)2.63
  • LogP (predicted, AB/LogP v2.0)2.58
  • pka7.2
  • LogD (pH=7, predicted)1.67
  • Solubility (experiment)N/A
  • LogS (predicted, ACD/Labs)(ph=7)-4.14
  • LogSw (predicted, AB/LogsW2.0)1.41
  • Sw (mg/ml) (predicted, ACD/Labs)0.01
  • No.of HBond Donors0
  • No.of HBond Acceptors7
  • No.of Rotatable Bonds6
  • TPSA69.64
  • StatusFDA approved
  • AdministrationN/A
  • PharmacologyA psychoactive drug and pharmaceutical medication of the piperazine and azapirone chemical classes. It is used primarily as an anxiolytic, but also to a lesser extent as an antidepressant.
  • Absorption_value100.0
  • Absorption (description)It is rapidly absorbed after oral administration; peak plasma concentrations occur after about 40 to 90 min.
  • Caco_2N/A
  • Bioavailability3.9
  • Protein binding95.0
  • Volume of distribution (VD)5.3 L/kg after a 20 mg intravenous dose
  • Blood/Plasma Partitioning ratio (D_blood)N/A
  • MetabollsmIt undergoes extensive first-pass metabolism primarily by oxidation and bioavailability is therefore low. Metabolism is probably mediated by CYP3A4. Most metabolites are inactive, although oxidative dealkylation produces 1-(2-pyrimidinyl)-piperazine which is about 20 to 25% as potent as the parent drug. The major metabolite is 5-hydroxybuspirone which may be oxidised further to many more metabolites and its glucuronide conjugate.
  • Half life2.4 h
  • ExcretionThe metabolites are excreted mainly in urine (65%); some are also excreted in faeces (35%). Less than 1% of a dose is excreted as the unchanged drug. It is not removed by haemodialysis.
  • Urinary Excretion<0.1
  • Clerance28.3 ml/min/kg
  • ToxicityOral, rat LD50 = 136 mg/kg. Symptoms of overdose include dizziness, drowsiness, nausea or vomiting, severe stomach upset, and unusually small pupils.
  • LD50 (rat)N/A
  • LD50 (mouse)N/A