Methysergide is an oral, synthetic ergot alkaloid, structurally related to the oxytocic agent methylergonovine and to the potent hallucinogen LSD. Methysergide is used prophylactically to reduce the frequency and intensity of severe vascular headaches. Although methysergide is an ergot alkaloid, it is a weak vasoconstrictor and oxytocic. Methysergide is a more potent antagonist of peripheral serotonin receptors than other ergot alkaloids. Methysergide is not just a 5HT2 antagonist, it is also a 5HT1 agonist. Although methysergide and sumatriptan both stimulate serotonin receptors centrally, methysergide is intended for prophylaxis while sumatriptan is indicated for treatment of an acute attack. Methysergide was approved by the FDA in 1962. Methysergide was formerly used for prophylaxis of cluster headaches/migraine headaches, but is no longer recommended due to retroperitoneal/retropulmonary fibrosis.

Methysergide is an oral, synthetic ergot alkaloid, structurally related to the oxytocic agent methylergonovine and to the potent hallucinogen LSD. Methysergide is used prophylactically to reduce the frequency and intensity of severe vascular headaches. Although methysergide is an ergot alkaloid, it is a weak vasoconstrictor and oxytocic. Methysergide is a more potent antagonist of peripheral serotonin receptors than other ergot alkaloids. Methysergide is not just a 5HT2 antagonist, it is also a 5HT1 agonist. Although methysergide and sumatriptan both stimulate serotonin receptors centrally, methysergide is intended for prophylaxis while sumatriptan is indicated for treatment of an acute attack. Methysergide was approved by the FDA in 1962. Methysergide was formerly used for prophylaxis of cluster headaches/migraine headaches, but is no longer recommended due to retroperitoneal/retropulmonary fibrosis.

Agomelatine behaves both as a potent agonist at melatonin MT1 and MT2 receptors and as a neutral antagonist at 5-HT2C receptors. Accumulating evidence in a broad range of experimental procedures supports the notion that the psychotropic effects of agomelatine are due to the synergy between its melatonergic and 5-hydroxytryptaminergic effects. Agomelatine is indicated for the treatment of major depressive episodes.

Agomelatine behaves both as a potent agonist at melatonin MT1 and MT2 receptors and as a neutral antagonist at 5-HT2C receptors. Accumulating evidence in a broad range of experimental procedures supports the notion that the psychotropic effects of agomelatine are due to the synergy between its melatonergic and 5-hydroxytryptaminergic effects. Agomelatine is indicated for the treatment of major depressive episodes.

Mianserin is a tetracyclic antidepressant used for the treatment of depression. It was investigated as an adjuvant for reduction of negative and cognitive symptoms of schizophrenia, as an aid for opioid detoxification therapy (where it reduced symptoms but lead to higher drop-out rate), and for the treatment of post-traumatic stress disorder (where it was ineffective). Mianserin has a broad spectrum of activity with the most potent binding to 5-HT2A, 5-HT2C, H1, alpha2A and alpha2C receptor.

Pizotifen (INN) or pizotyline (USAN), trade name Sandomigran, is a benzocycloheptene-based drug used as a medicine, primarily as a preventative to reduce the frequency of recurrent migraine headaches. Pizotifen is a serotonin antagonist acting mainly at the 5-HT2A and 5HT2C receptors. It also has some activity as an antihistamine as well as some anticholinergic activity. The main medical use for pizotifen is for the prevention of vascular headache including migraine and cluster headache. Pizotifen is one of a range of medications used for this purpose, other options include propranolol, topiramate, valproic acid and amitriptyline. While pizotifen is reasonably effective, its use is limited by side effects, principally drowsiness and weight gain, and it is usually not the first choice medicine for preventing migraines, instead being used as an alternative when other drugs have failed to be effective. It is not effective in relieving migraine attacks once in progress. Pizotifen has also been reported as highly effective in a severe case of erythromelalgia, a rare neurovascular disease that is sometimes refractory to the other drugs named above. Side effects include sedation, dry mouth, drowsiness, increased appetite and weight gain. Occasionally it may cause nausea, headaches, or dizziness. In rare cases, anxiety, aggression and depression may also occur. Pizotifen is well absorbed from the gastro-intestinal tract, peak plasma concentrations occurring approximately 5 hours after oral administration. The absorption of pizotifen is fast (absorption half life 0.5 to 0.8 hours) and nearly complete (80%). Over 90% is bound to plasma proteins. Pizotifen undergoes extensive metabolism. Over half of a dose is excreted in the urine, chiefly as metabolites; a significant proportion is excreted in the faeces. The primary metabolite of pizotifen (N-glucuronide conjugate) has a long elimination half-life of about 23 hours.

Setiptiline Maleate is a tetracyclic antidepressant that has been used in the treatment of depression. It has antihistamine and hypnotic–sedative effects, but almost no anticholinergic effects. It is a weak inhibitor of norepinephrine reuptake in vitro and strongly stimulates the release of central norepinephrine by blocking presynaptic α2-adrenoceptors similar to mianserin. It also acts as a 5-HT2A, 5-HT2C, and 5-HT3 receptor antagonist. Unlike most conventional antidepressants, it has no efficacy as a serotonin reuptake inhibitor. It can induce drowsiness and thirst, but it displays low toxicity. Setiptiline Maleate was launched in 1989 for the treatment of depression in Japan.

Pizotifen (INN) or pizotyline (USAN), trade name Sandomigran, is a benzocycloheptene-based drug used as a medicine, primarily as a preventative to reduce the frequency of recurrent migraine headaches. Pizotifen is a serotonin antagonist acting mainly at the 5-HT2A and 5HT2C receptors. It also has some activity as an antihistamine as well as some anticholinergic activity. The main medical use for pizotifen is for the prevention of vascular headache including migraine and cluster headache. Pizotifen is one of a range of medications used for this purpose, other options include propranolol, topiramate, valproic acid and amitriptyline. While pizotifen is reasonably effective, its use is limited by side effects, principally drowsiness and weight gain, and it is usually not the first choice medicine for preventing migraines, instead being used as an alternative when other drugs have failed to be effective. It is not effective in relieving migraine attacks once in progress. Pizotifen has also been reported as highly effective in a severe case of erythromelalgia, a rare neurovascular disease that is sometimes refractory to the other drugs named above. Side effects include sedation, dry mouth, drowsiness, increased appetite and weight gain. Occasionally it may cause nausea, headaches, or dizziness. In rare cases, anxiety, aggression and depression may also occur. Pizotifen is well absorbed from the gastro-intestinal tract, peak plasma concentrations occurring approximately 5 hours after oral administration. The absorption of pizotifen is fast (absorption half life 0.5 to 0.8 hours) and nearly complete (80%). Over 90% is bound to plasma proteins. Pizotifen undergoes extensive metabolism. Over half of a dose is excreted in the urine, chiefly as metabolites; a significant proportion is excreted in the faeces. The primary metabolite of pizotifen (N-glucuronide conjugate) has a long elimination half-life of about 23 hours.

Pipamperone (INN, USAN, BAN), also known as Carpiperone and Floropipamide or Fluoropipamide, and as Floropipamide hydrochloride (JAN), is a typical antipsychotic of the butyrophenone family used in the treatment of schizophrenia. It is or has been marketed under brand names including Dipiperon, Dipiperal, Piperonil, Piperonyl, and Propitan. Pipamperone acts as an antagonist of the 5-HT2A, 5-HT2B, 5-HT2C D2, D3, D4, α1-adrenergic, and α2-adrenergic receptors. It shows the much higher affinity for the 5-HT2A and D4 receptors over the D2receptor (15-fold in the case of the D4 receptor, and even higher in the case of the 5-HT2A receptor), is regarded as "highly selective" for the former two sites at low doses. Pipamperone has low and likely insignificant affinity for the H1 and mACh receptors, as well as for other serotonin and dopamine receptors. Low-dose pipamperone (5 mg twice daily) has been found to accelerate and enhance the antidepressant effect of citalopram. Pipamperone is approved in some European countries. At its usually recommended antipsychotic dose (120–360 mg/d), it has relatively weak neuroleptic activity because it is only moderately effective as a dopamine D2-receptor antagonist, even at high doses.

Dimebon (latrepirdine) is an orally available, small molecule, gamma carboline derivative that was developed and used in Russia as an over-the-counter oral antihistamine for allergy treatment since 1980s. In 1990s it was shown that Dimebon has promising potential in treating neurodegenerative diseases. In 2003, Medivation Inc acquired the rights to Dimebon. Medivation went public in December 2004, with Dimebon as the only drug in its pipeline. The product was being developed by Medivation and Pfizer as a treatment for early-stage Alzheimer's disease and Huntington's disease. However, development was discontinued by Medivation and Pfizer in early 2012. Dimebon inhibits alpha-Adrenergic receptors (alpha1A, alpha1B, alpha1D, and alpha2A), Histamine H1 and H2 receptors and Serotonin 5-HT2c, 5-HT5A, 5-HT6 receptors with high affinity. Dimebon may act by blocking NMDA receptors or voltage-gated Ca2+ channels and by preventing mitochondrial permeability pore transition.