Prolonged hypotension and disseminated intravascular coagulation were seen in a patient after intravasation of barium sulfate contrast medium during a barium enema examination. High endotoxin levels were measured in the contrast material. In vitro, this material induced generation of bradykinin. The clinical features observed may be explained by contact activation of the Hageman factor-dependent pathways caused by the contrast material and/or by circulating endotoxins. Treatment of this rare but severe complication occurring during a barium enema procedure should be directed against the endotoxic shock.