Propisergide (INNTooltip International Nonproprietary Name; developmental code name PML-946), also known as ergalgin or as N-methylergometrine or 1-methylergometrine, is a serotonin receptor modulator and antimigraine agent of the ergoline and lysergamide families which was never marketed. It is the 1-methyl derivative of ergometrine (ergonovine) and is a close analogue of methylergonovine and methysergide (UML-491). Extensive metabolism of other 1-methylated lysergamides to their secondary amine derivatives, for instance methysergide (1-methylmethylergometrine) conversion into methylergometrine, has been observed. Propisergide has 259% of the antiserotonergic activity of LSD. Its average clinical dose range for preventative treatment of migraine is 1 to 3 mg orally. Propisergide was first described in the literature by 1958 and then further around 1980 and after.