The salts of caffeine and theobromine, although known for many years, did not come into general use as diuretics until after the publications of von Schroeder,1 Filehne,2 Langgaard,3 Gram,4 and others, beginning in 1885 and extending over the next few years. The therapeutic use of these drugs for symptoms directly cardiac in origin did not receive definite attention until ten years later. In 1895, Askanazy,5 in an article dealing with the diuretic effects of theobromine sodiosalicylate, reported ten cases with varying pathologic changes in which this drug was used for the relief of cardiac asthma and of angina pectoris. "By the use of these drugs," he states, "attacks of cardiac asthma with or without the phenomena of angina pectoris may be terminated. In some the effect was exceedingly striking."
Apparently little attention was attracted by Askanazy's results until 1902, when Breuer,6 in an article