Buspirone
Buspirone. 5-HT1A partial agonist — generalized anxiety treatment without GABA-A activation, so no sedation, no abuse, no addiction. Onset over… Oral half-life 2.5 h.
5-HT1A partial agonist — generalized anxiety treatment without GABA-A activation, so no sedation, no abuse, no addiction. Onset over weeks like an SSRI; acute anxiety relief is poor. CYP3A4 substrate.
PK: THE BACKLOG SUSPICION AGAINST THIS RECORD IS REFUTED AND THE REAL DEFECT IS SOMEWHERE ELSE. Section 11 flagged it as the most sensitive consumer of the double-division; it is not. Its own arithmetic clears it: F times dose divided by V gives 0.00211 mg/L against a measured peak of "approximately 2.5 micrograms/L", a 16% shortfall which is the ordinary shape of a steady-state volume in a one-compartment model — WERE F APPLIED TWICE THE MODEL WOULD PREDICT ABOUT A TWENTY-FIFTH OF THAT. So the pairing is right. Its citation, however, is a grapefruit-juice interaction study stating only fold-changes; both surviving values are verbatim elsewhere, "The absolute bioavailability of buspirone is approximately 4%" and "an elimination half-life of about 2.5 hours". V 380 L is 5.3 L/kg times an assumed 71.7 kg, computed. ka 1.5 predicts a 1.38 h peak against its own citation verbatim 0.75 h. CLASS 5 IS ALSO LIVE AND UNMODELLED: metabolite exposures run "approximately 12 ... and 49 ... fold higher than the exposure of the parent". THE OCCUPANCY ROW IS THE URGENT DEFECT — see the receptor block.
Pharmacokinetics
- Oral — t½ 2.5 h · F 4% · Vd 380 L
Sources: PMID:9871430, PMID:7647978, PMID:10320950, PMID:11401009, PMID:17494642