A serotonin antagonist, or serotonin receptor antagonist, is a drug used to inhibit the action of serotonin and serotonergic drugs at serotonin (5-HT) receptors.
Types
5-HT2A antagonists Antagonists of the 5-HT2A receptor are sometimes used as atypical antipsychotics (contrast with typical antipsychotics, which are purely dopamine antagonists).
They include, but are not limited to:
Cyproheptadine blocks 5-HT2A, H1 and is a mild anticholinergic. Methysergide is a 5-HT2A antagonist and nonselective 5-HT1 receptor blocker. It causes retroperitoneal fibrosis and mediastinal fibrosis. Quetiapine blocks 5-HT2A, 5-HT1A, dopamine receptors D1 and D2, histamine receptor H1, and a1 adrenoreceptors.
5-HT2A/2C antagonists Ketanserin Antihypertensive. Blocks 5-HT2A, 5-HT2C and Alpha 1 (a1) adrenoreceptors. Risperidone antipsychotic Trazodone Nefazodone
5-HT3 antagonists Another subclass consists of drugs selectively acting at the 5-HT3 receptors, and thus are known as 5-HT3 antagonists. They are effective at treating chemotherapy-induced emesis and postoperative nausea and vomiting.
They include, but are not limited to:
Dolasetron Granisetron Ondansetron Palonosetron Tropisetron
Other 5-HT3 antagonists have been considered for use in the treatment of irritable bowel syndrome:
Alosetron Cilansetron
Also, the antidepressant mirtazapine acts as a 5-HT3 antagonist.
Non-selective 5-HT antagonists Although some non-selective serotonin antagonists may have a particular affinity for a specific 5-HT receptor (and thus may be listed below e.g., methysergide), they still may also possess a generalised non-selective action.
They include, but are not limited to:
Chlorpromazine Cyproheptadine Metergoline Methysergide Mianserin Mirtazapine Oxetorone Pizotifen Propranolol Ritanserin Spiperone
Antihistamines with antiserotonergic activity Carbinoxamine Cinnarizine Cyproheptadine Hydroxyzine Methdilazine Pizotifen Promethazine Pizotifen is a 5-HT2C antagonist, H1 blocker and anticholinergic useful in migraine prophylaxis. Oxatomide Oxetorone Also used in the treatment of migrane. Ketotifen
Others Fenclonine (para-chlorophenylalanine; PCPA) An inhibitor of serotonin synthesis that has been used in the treatment of carcinoid syndrome. Feverfew Is a herb traditionally used for migraines (contains parthenolide). Reserpine Depletes serotonin stores in the brain, heart, and many other organs and has been used in hypertension and psychosis Gamma-mangostin from Garcinia mangostana
See also Serotonin receptor agonist
References
External links