SB 243213 dihydrochloride is an orally active, selective and high-affinity antagonist of 5-hydroxytryptamine (5-HT)2C receptor(pKi of 9.37 and a pKb of 9.8 for human 5-HT2C receptor).

5-HT2C receptor:9.37 (pki)

SB 243213 dihydrochloride shows little affinity with pKi less than 6 for cloned human 5-HT1A, 5-HT1B, 5-HT1E, 5- HT1F and 5-HT7 receptors. It shows weak affinity (pKi<6.5) for the cloned human 5-HT1D and D3 receptors and moderate affinity (pKi=6.7) for the cloned human D2 receptor.

SB 243213 dihydrochloride (0.3 mg/kg; p.o.; 1 h pre-test) significantly increases time spent in social interaction. SB 243213 dihydrochloride (0.1-10 mg/kg; p.o.; 1 h pre-test) dose-dependently and significantly increases the amount of time rats spent in social interaction over 15 min under brightly lit conditions and in an unfamiliar test box.