A clamp adapter for a catheter has a clamp body (10) that receives anelastomericclamp bushing. In order to fix a catheter inserted into the clamp bushing, theclampbushing is axially compressed by a clamp lid (24). For this purpose, the clamplid(24) is moved axially on the clamp body (10) with a clamp lever (30) by meansof aslotted guide (42, 44).