Aceprometazine (INN) is a prescription drug with neuroleptic and anti-histamine properties. It is not widely prescribed. It may be used in combination with meprobamate for the treatment of sleep disorders. This combination is available in France under the trade name Mepronizine. [Wikipedia] (en)
Aceprometazine, acting as an H1-receptor antagonist can induce sedation by being able to cross the blood-brain-barrier and binding to H1-receptors in the central nervous system. (en)