Dipyridamole, bleeding risk

The AHA/ASA guidelines recommend that antiplatelet therapy as the cornerstone of antithrombotic therapy for the secondary prevention of ischemic stroke and should be used in noncardioembolic strokes. Aspirin, dopidogrel, and extended-release dipyridamole plus aspirin are all considered first-line antiplatelet agents (see Table 13-1). The combination of aspirin and clopido-grel can only be recommended in patients with ischemic stroke and a recent history of myocardial infarction or coronary stent placement and then only with ultra-low-dose aspirin to minimize bleeding risk. 

Administration of the thrombolytic drugp with aspirin, dipyridamole, or the anticoagulants may increase the risk of bleeding. 

Medications known to increase the risk of bleeding in cirrhotic patients include aspirin, clopidogrel, dipyridamole, corticosteroids, NSAIDs, heparin and warfarin. Mrs MW would need to be counselled about the risks associated with these medications and advised to always check with the pharmacist before buying any medications over the counter. 

ASPIRIN ANTIPLATELET AGENTS Risk of bleeding when aspirin is co administered with other antiplatelet agents. The addition of dipyridamole to low-dose aspirin does not seem to confer an t risk of bleeding Additive effect Closely monitor effects watch for signs of excess bleeding... 

DIPYRIDAMOLE PERIPHERAL VASODILATORS Possible T risk of bleeding with cilostazol. Additive effect cilostazol has antiplatelet activity Warn the patient to report any signs of t bleeding. 

CILOSTAZOL CLOPIDOGREL, DIPYRIDAMOLE, GLYCOPROTEIN lib/ Ilia INHIBITORS Possible t risk of bleeding with cilostazol Additive effect cilostazol has antiplatelet activity. Clopidogrel t the levels of a metabolite of cilostazol that has high antiplatelet activity, by an uncertain mechanism Warn the patient to report any signs of t bleeding... 

Risk of bleeding or hemorrhage is increased with concommitant administration of aspirin, ibuprofen, anticoagulants/thrombolytics, dextran, phenylbutazone, indomethacin, dipyridamole, several penicillins and cephalosporins, valproic acid, divalproex, plicamycin, methimazole, propylthiouracil, probenecid, hydroxychloroquine, chloroquine. Decreased anticoagulation effect with digitalis, tetracyclines, antihistamines, nicotine. 

The combination of dipyridamole and coumarin anticoagulants does not alter the prothrombin time, but might cause an increased risk of serious bleeding when compared with anticoagulants alone. There is some evidence that the risk of bleeding may be lower, without a reduction in efficacy, if the INR is maintained within a lower range. 

In one randomised study, the risk of excessive bleeding was 4% in patients taking warfarin and dipyridamole 400 mg daily, compared with 14% in patients taking warfarin and aspirin 500 mg daily. When compared with a non-randomised control group taking warfarin alone, the risk... 

Dipyridamole reduces platelet adhesiveness or aggregation, which prolongs bleeding time. This may increase the risk or severity of bleeding if overanticoagulation occurs. 

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