Melorazine was a standard sedative.
According to his medical file, Spock's physician recommended that he be treated with melorazine, as well as dylamadon, axonol, tetrovaline, and cortropine, when he had himself admitted to the psychiatric ward of Starbase 5. (DIS: "Point of Light")
In 2369, Nurse Ogawa administered a dose of twenty ccs to Deanna Troi in order to stop her struggles while she was being treated in a biobed. (TNG: "Man Of The People")