Abstract: | The combination of acetylsalicylic acid with aminophenazone, often prescribed in divided powders, is considered to be incompatible. High performance liquid chromatography was applied to determine the content of salicylic acid which is the main known product from the decomposition of acetylsalicylic acid. The analysis of model samples containing a 1:1 (by weight) mixture of acetylsalicylic acid and aminophenazone, after having been stored under usual conditions in starch capsules, showed that the decomposition of acetylsalicylic acid into salicylic acid did not exceed 0.8% even after ten weeks. |