Tipepidine hydrochloride reversibly inhibits dopamine (DA) D2 receptor-mediated GIRK currents (IDA(GIRK)) with an IC50 of 7.0 μM. Tipepidine hydrochloride subsequently activates VTA dopamine neuron. Tipepidine hydrochloride, a non-narcotic antitussive, exerts an antidepressant-like effect[2].IC50 & Target: IC50: 7.0 μM (dopamine D2 receptor)In Vivo: Tipepidine (i.p.; 10-40 mg/kg; 0.5-23 hours) significantly decreases the immobility time in the forced swimming test in ACTH-treated rats. Tipepidine (i.p.; 40 mg/kg) increases the extracellular dopamine level of the nucleus accumbens (NAc) in ACTH-treated rats[2].