<p>The vasodilating effects of nitroglycerin may be additive with those of other vasodilators. Administration of nitroglycerin infusions through the same infusion set as blood can result in pseudoagglutination and hemolysis. More generally, nitroglycerin in 5% dextrose or sodium chloride 0.9% should not be mixed with any other medication of any kind. Intravenous nitroglycerin interferes, at least in some patients, with the anticoagulant effect of heparin. In patients receiving intravenous nitroglycerin, concomitant heparin therapy should be guided by frequent measurement of the activated partial thromboplastin time.</p>