Anti-platelet drugs have been used to prevent thrombosis of systemic to pulmonary artery shunts. Aspirin has traditionally been used. Clopidogrel is being studied as an alternative and in combination with aspirin for shunt patients. We report a near fatal gastro-intestinal bleed in a patient with shunt and on aspirin and clopidogrel. This combination has been known to produce similar bleeds. The authors recommend caution in combining them. Prospective studies currently underway should evaluate this aspect of the antiplatelet drugs.