title: [Effects of cimetidine and ranitidine on blood coagulation].
abstract: The influence of cimetidine and ranitidine on blood coagulation and plasmatic fibrinolysis were assessed in vitro and in vivo. After an intravenous bolus of 200 mg cimetidine a marked prolongation of plasmatic thrombin time was observed, which however did not occur after 50 mg of ranitidine. In vitro addition of cimetidine (0.12 mg/ml) and ranitidine (0.06 mg/ml) again led to prolongation of plasmatic thrombin time only after cimetidine, reaching double the initial value. This requires application of cimetidine in acute intestinal haemorrhage not as a bolus, but only by drip infusion. Continuous application of 600 mg over 12 hours did not result in changes of coagulation values. In contrast, ranitidine may be administered as a bolus. Bolus injections of 50 to 100 mg did not result in any prolongation of plasmatic thrombin time. The antifibrinolytic effect of both H2-receptor antagonists was investigated in the streptokinase-induced fibrinolysis spindle of the thrombelastogram. Clear-cut antifibrinolytic properties were not demonstrable for either preparation with this method.
mesh_terms: D001777:Blood Coagulation / Q000187:drug effects*; D002927:Cimetidine / Q000494:pharmacology*; D005342:Fibrinolysis / Q000187:drug effects; D005663:Furans / Q000494:pharmacology*; D006146:Guanidines / Q000494:pharmacology*; D006801:Humans; D011899:Ranitidine; D013916:Thrombelastography; D013918:Thrombin Time
chemical_list: D005663:Furans; D006146:Guanidines; D002927:Cimetidine; D011899:Ranitidine
vernacular_title: Auswirkungen von Cimetidin und Ranitidin auf die plasmatische Gerinnungsfähigkeit des Blutes.