Betahistine (0-10 μM) inhibits [ 125 I]iodoproxyfan binding to membranes of CHO (rH 3(445) R) and CHO (hH 3(445) R) cells with IC 50 values of 1.9 μM and 3.3 μM, respectively. Lead to K i values of 1.4 μM and 2.5 μM, respectively.