Name: Buspirone (Bu Spar)
Class: Antianxiety-Sedative-Hypnotic Agents (Selective Antianxiety Agent)
Mechanism: Agonist for 5-HT 1A and D2 receptors.
Absorption: Oral ® rapid absorption.
Dist.:
Metabolism.: Extensive 1st-pass Metabolism. (hepatic hydroxylation & dealkylation) ® Metabolismolites that may have slight activity.
Excretion, t½: 2-4 hr.
Toxicity/S.E.s: Wide safety margin. Dizziness, insomnia, nervousness, nausea, headache, myoclonic jerks, chest pain, tinnitus, fatigue. Lower incidence of CNS S.E.s than w/BZDs, but higher incidence of GI S.E.s. Coadmin. w/haloperidol ® serum haloperidol. W/MAO inhib. may cause BP.
Utility: Short-term relief of anxiety w/o signif. sedation, drowsiness, or amnesia.
Special Features: No synergistic/additive effect w/other antianxiety or hypnotic agents. No CNS depression. No known potential for tolerance, dependence, abuse, or withdrawal. May take more than a week for anxiolytic effects to develop.