Drug/Small Molecule:

buspirone

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. PubChem (source: Drug Bank)

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. (source: Drug Bank)

Buspirone 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. Buspirone also binds at dopamine type 2 (DA2) receptors, blocking presynaptic dopamine receptors. Buspirone 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. (source: Drug Bank)

Buspirone 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. Buspirone 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. <i>in vitro</i> preclinical studies have shown that buspirone has a high affinity for serotonin (5-HT_1A) receptors. Buspirone has no significant affinity for benzodiazepine receptors and does not affect GABA binding <i>in vitro</i> or <i>in vivo</i> when tested in preclinical models. Buspirone has moderate affinity for brain D2-dopamine receptors. Some studies do suggest that buspirone may have indirect effects on other neurotransmitter systems. (source: Drug Bank)

Always take at the same time with respect to meals.
Avoid alcohol.
Avoid taking grapefruit or grapefruit juice throughout treatment.
Take with food. (source: Drug Bank)

Metabolized hepatically, primarily by oxidation by cytochrome P450 3A4 producing several hydroxylated derivatives and a pharmacologically active metabolite, 1-pyrimidinylpiperazine (1-PP) (source: Drug Bank)

95% (approximately 70% bound to albumin, 30% bound to alpha 1 -acid glycoprotein) (source: Drug Bank)

Rapidly absorbed in man. Bioavailability is low and variable (approximately 5%) due to extensive first pass metabolism. (source: Drug Bank)

Oral, rat LD₅₀ = 136 mg/kg. Symptoms of overdose include dizziness, drowsiness, nausea or vomiting, severe stomach upset, and unusually small pupils. (source: Drug Bank)

c1cnc(nc1)N2CCN(CC2)CCCCN3C(=O)CC4(CCCC4)CC3=O (source: Drug Bank)