Agents for Serotonergic Neurotransmission Inhibitors of serotonin storage –Amphetamine, methylphenidate, modafinil –Fenfluramine, dexfenfluramine –Methylenedioxymethamphetamine (MDMA, “ecstasy”) Inhibitors of serotonin degradation –MOAI, RIMA Reuptake inhibitors –TCAs: NET and SERT blocker with anticholinergic, antiadrenergic and antihistaminergic action –SSRIs: fluoxetine, citalopram, fluvoxamine, paroxetine, sertraline, escitalopram –SNRIs: venlafaxine, duloxetine Atypical antidepressants –Bupropion, mirtazapine: 5HT 2A/2C R and alpha2 R blocker, nefazodone: 5HT 2 R blocker, trazodone: 5HT 2 R blocker Serotonin receptor agonists Serotonin receptor antagonists

Serotonin receptor agonists Ergots from the rye rust fungus Clasviceps purpurea: 5HTRs agonists –intense vasoconstriction -> ergotism: necrosis and gangrene Lysergic acid diethylamide (LSD), a semisynthetic ergot: 5HT Rs agonist –hallucinations and sensory dysfunction Buspirone: 5HT 1A R agonist –to treat anxiety and migraine headache Triptans - sumatriptan, riztriptan, almotriptan, frovatriptan, eletriptan, zolmitriptan: 5HT 1B/1D R agonists –to treat migraine headache Trazodone  meta-chlorophenylpiperazine (mCPP): 5HT 2A/2C R agonist –to treat depression and insomnia Cisapride: 5HT 4 R agonist –GI motility

Serotonin receptor antagonists Ketanserin: 5HT 2A/2C R antagonist with alpha- adrenergic activity –topical; in glaucoma Ondansetron: 5HT 3 R antagonist; chemo-trigger zone –antiemetic Alosetron: 5HT 3 R antagonist –use for diarrhea associated with IBS Tegaserod, prucalopride: 5HT 4 R antagonist –to treat constipation associated with irritable bowel syndrome (IBS)

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