Aspirin

Abstract

Acetylsalicylic acid (aspirin) was the first synthetized drug 100 years ago. Whereas other drugs have disappeared a long time ago, aspirin has stood the test of time and is one of the most important drugs at the turn of this century. Initially it was used for its analgesic, antipyretic and antiphlogistic properties. They are due to the acetylation of the cyclooxygenase and hence an inhibition of prostaglandin synthesis. At higher doses aspirin inhibits interleukin expression induced by nuclear factor-kappa B. Aspirin is the prototype of nonsteroidal antiinflammatory drugs, which are currently challenged by the development of specific inhibitors of cyclooxygenase isoform 2 (COX-2), which must, however, first prove their efficacy and safety in clinical trials. The inhibition of platelet aggregation by aspirin has only been recognized in the second half of the century. It is due to an inhibition of thromboxane A2 synthesis because of an irreversible cyclooxygenase blockade in platelets. Aspirin has been found to reduce the incidence and death rate of cardiovascular and cerebrovascular events and is nowadays the cornerstone of any secondary prevention in vascular diseases. Newer antiaggregatory agents such as ticlopidine, clopidogrel or IIb/IIIa-blockers have been developed. Most often they are used in conjunction with aspirin and their place has yet to be defined. New modes of action of aspirin continue to be found. Recent examples are an improvement of endothelial dysfunction or a reduced incidence of colorectal cancers. It is therefore likely that aspirin will continue to be a very useful and cheap drug for a very large population and will meet the interest of researchers for many more decades.