A serotonin antagonist is a drug used to inhibit the action at serotonin (5-HT) receptors.
- Cyproheptadine blocks 5-HT2A, HI 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.
- ketanserin Antihypertensive. Blocks 5-HT2A, 5-HT2C and Alpha 1 (A1) adrenoreceptors.
- Risperidone antipsychotic
- Trazodone antidepressant
- Clozapine antipsychotic. Blocks 5-HT2A, 5-HT2C and D4 receptors.
Another subclass consists of drugs selectively acting at the 5-HT3 receptors, and thus are known as 5-HT3 antagonists. They are efficacious in treating chemotherapy-induced emesis and postoperative nausea and vomiting. They include:
Other 5-HT3 antagonists are used for the treatment of irritable bowel syndrome:
Non-selective 5-HT antagonists
Please note, that although some non-selective serotonin antagonists may have an particular affinity for a specific 5-HT receptor (and thus may be listed above eg methysergide), they still may also possess a generalised non-selective action.
Serotonin anatagonists acting as antihistamines for allergic conditions
- Pizotifen is a 5-HT2C antagonist, H1 blocker and anticholinergic useful in migraine prophylaxis. Also used in the treatment of migrane.
- cyproheptadine Also used in the treatment of migrane.
- oxetorone Also used in the treatment of migrane.
- Feverfew Is a herb traditionally used for migraines.
- Fenclonine An inhibitor of serotonin synthesis that has been used in the treatment of carcinoid syndrome.
- Reserpine Depletes serotonin stores in the brain, heart, and many other organs and has been used in hypertension and psychoses
- Serotonin Antagonists at the US National Library of Medicine Medical Subject Headings (MeSH)
- MeSH list of agents 82012702