[Aspirin. Acetylsalicylic acid and aspirinlike drugs. A review.].

In this review acetylsalicylic acid and aspirin with little "a" are considered as synonyms. A short acount is given of the history preceeding the synthesis of acetylsalicylic acid from salicylic acid by Felix Hoffmann in 1897 and its marketing in 1899 as Aspirin(R) by the Bayer Company. Aspirin was originally considered a prodrug to salicylic acid since it was at that time thought to have the same pharmacodynamic effects as salicylic acid and is rapidly transformed to it in vivo. Later aspirin was also found to be effective in its own right. During the years aspirin has gradually become the standard drug among an increasing number of aspirinlike drugs having similar effects as aspirin and often collectively, and somewhat misleading, named "nonsteroidal antiinflammatory drugs" (NSAIDs). The seminal work of John Vane and his colleagues in the 1970s and later has irrefutably tied the effects and side effects of aspirin and aspirinlike drugs to blocking of cyclooxigenase activity and therefore to reduced production of prostaglandins and related biogenic lipids. The anticoagulant effect, where aspirin itself is the cardinal drug, is thus due to decreased synthesis of thromboxan, whereas the antipyretic effect is due to reduced synthesis of prostaglandins in the central nervous system. The analgesic effect is obviously both related to decreased synthesis of prostaglandins in the central nervous system and outside it. On the other hand the antiinflammatory effect is seemingly mostly due to blocking inflammatory phenomena, without involvement of cyclooxigenase, in the walls of vessels although blocking the synthesis of prostaglandins also has a role. All aspirinlike drugs have until quite recently been mixed blockers of cyclooxigenases (COX 1 and COX 2) with aspirin itself being the most outstanding COX 1 blocker. New aspirinlike drugs with selective COX 2 blocking effect are apparently not any better on classical indications than the older drugs with mixed COX 1 and COX 2 blocking effect and their use might moreover be limited by some severe side effects. These drugs might, however, become of value for use on new indications.