Mesdopetam (IRL790), a dopamine D3 receptor antagonist with a Ki of 90 nM and an IC50 of 9.8 μM for the human recombinant D3 receptor, exhibits psychomotor stabilizing properties and is used in the study of motor and psychiatric complications associated with Parkinson's disease.

Mesdopetam (IRL790) (3.7, 11, 33, or 100 μmol/kg) dose-dependently inhibits behavioral activation following pretreatment with D-amphetamine or MK-80[1]. Mesdopetam (10 mg/kg; intraperitoneally; fourteen-week-old male C57BL/J mice) promotes a sedative effect similar to haloperidol, significantly reducing total distance traveled and average speed[2]. In male Sprague-Dawley rats, synthesized mesdopetam (HCl salt, dissolved in 0.9% saline) administered subcutaneously (3.7, 11, 33, or 100 μmol/kg) 4 minutes before recording, dose-dependently inhibited behavioral activation following pretreatment with D-amphetamine or MK-801[1].