Wiktionary
n. A tetracyclic antidepressant with antihistaminic and hypnosedative properties.
Wikipedia
Mianserin (brand names: Depnon ( IN), Lantanon ( ZA), Lerivon ( AR, BE, CZ, PL, RU, SK), Lumin ( AU), Norval ( UK), Tolvon ( AU, HK, IE, NZ, SG), Tolmin ( DK); where † indicates discontinued products) is a psychoactive drug of the tetracyclic antidepressant (TeCA) therapeutic family. It is classified as a noradrenergic and specific serotonergic antidepressant (NaSSA) and has antidepressant, anxiolytic (anti-anxiety), hypnotic (sedating), antiemetic (nausea and vomiting-attenuating), orexigenic (appetite-stimulating), and antihistamine effects.
It is not approved for use in the US, but its analogue, mirtazapine, is. Mianserin was the first antidepressant to reach the UK market that was less dangerous than the tricyclic antidepressants in overdose.