Heparin and heparinoids constitute the one drug group shown to arrest and reverse atherosclerotic changes in rabbits on a high cholesterol/fat diet. Little use has been made of this finding because heparin has been administered by routes which produce anticoagulation and thus bleeding. Inhalation once a fortnight results in a high concentration of heparin in endothelium with low plasma concentrations. No toxicity has been demonstrated with long term heparin but this is not true for heparinoids.
