A serotonin antagonist, or serotonin receptor antagonist, is a drug used to inhibit the action at serotonin (5-HT) receptors.

Types

5-HT_2A antagonists

Antagonists of the 5-HT_2A 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-HT_2A, H1 and is a mild anticholinergic. * Methysergide is a 5-HT_2A antagonist and nonselective 5-HT₁ receptor blocker. It causes retroperitoneal fibrosis and

mediastinal fibrosis Mediastinal fibrosis most common cause is idiopathic mediastinal fibrosis; less commonly histoplasmosis tuberculosis or unknown. It is characterized by invasive, calcified fibrosis centered on lymph nodes that block major vessels and airways. In ...

. * Quetiapine blocks 5-HT_2A, 5-HT_1A, dopamine receptors D₁ and D₂, histamine receptor H1, and A1 adrenoreceptors.

5-HT_2A/2C antagonists

* Ketanserin Antihypertensive. Blocks 5-HT_2A, 5-HT_2C and Alpha 1 (A1) adrenoreceptors. * Risperidone antipsychotic * Trazodone

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 efficacious in treating chemotherapy-induced emesis and postoperative nausea and vomiting. They include, but are not limited to: * Dolasetron *

Granisetron Granisetron is a serotonin 5-HT3 receptor antagonist used as an antiemetic to treat nausea and vomiting following chemotherapy and radiotherapy. Its main effect is to reduce the activity of the vagus nerve, which is a nerve that activates the v ...

* Ondansetron * Palonosetron * Tropisetron Other 5-HT₃ antagonists are used for the treatment of irritable bowel syndrome: * Alosetron *

Cilansetron Cilansetron is an experimental drug that is a 5-HT3 antagonist under development by Solvay Pharmaceuticals. 5-HT3 receptors are responsible for causing many things from nausea to excess bowel movements. In conditions such as irritable bowel s ...

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 Metergoline (, ), also known as methergoline and sold under the brand names Contralac (veterinary) and Liserdol (clinical), is a monoaminergic medication of the ergoline group which is used as a prolactin inhibitor in the treatment of hyperprola ...

* Methysergide *

Mianserin Mianserin, sold under the brand name Tolvon among others, is an atypical antidepressant that is used primarily in the treatment of depression in Europe and elsewhere in the world. It is a tetracyclic antidepressant (TeCA). Mianserin is close ...

* Mirtazapine * Oxetorone * Pizotifen * Propranolol *

Ritanserin Ritanserin, also known by its developmental code name R-55667, is a serotonin antagonist medication described as an anxiolytic, antidepressant, antiparkinsonian agent, and antihypertensive agent. It was never marketed for medical use due to sa ...

* Spiperone

Antihistamines with antiserotonergic activity

Carbinoxamine Carbinoxamine is an antihistamine and anticholinergic agent. It is used for hay fever, vasomotor rhinitis, mild urticaria, angioedema, dermatographism and allergic conjunctivitis. Carbinoxamine is a histamine antagonist, specifically an H1-antago ...

* Cyproheptadine * Hydroxyzine *

Methdilazine Methdilazine (Dilosyn, Tacaryl) is a first-generation antihistamine with anticholinergic properties of the phenothiazine class. Synthesis See also * Phenothiazine Phenothiazine, abbreviated PTZ, is an organic compound that has the formula ...

* Pizotifen * Promethazine * Pizotifen is a 5-HT_2C antagonist, H1 blocker and anticholinergic useful in

migraine Migraine (, ) is a common neurological disorder characterized by recurrent headaches. Typically, the associated headache affects one side of the head, is pulsating in nature, may be moderate to severe in intensity, and could last from a few hou ...

prophylaxis. Also used in the treatment of migrane. *

Oxatomide Oxatomide, sold under the brand name Tinset among others, is a first-generation antihistamine of the diphenylmethylpiperazine family which is marketed in Europe, Japan, and a number of other countries. It was discovered at Janssen Pharmaceutica ...

* 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 ''Tanacetum parthenium'', known as feverfew, is a flowering plant in the daisy family, Asteraceae. It may be grown as an ornamental plant, ornament, and may be identified by its synonyms, ''Chrysanthemum parthenium'' and ''Pyrethrum parthenium' ...

Is a herb traditionally used for migraines (contains parthenolide). *

Reserpine Reserpine is a drug that is used for the treatment of high blood pressure, usually in combination with a thiazide diuretic or vasodilator. Large clinical trials have shown that combined treatment with reserpine plus a thiazide diuretic reduces m ...

Depletes serotonin stores in the brain, heart, and many other organs and has been used in hypertension and psychosis * Gamma-mangostin from Garcinia mangostana

References

External links

* * {{nervous-system-drug-stub

Types

5-HT2A antagonists

5-HT2A/2C antagonists

5-HT3 antagonists