These two belong to the same chemical group, methylxanthenes. Both have similar properties, However they are antagonists. During 1800s caffeine was the prime anti-asthmatic drug to dilate bronchial tubes, but in 1920s theophylline replaced caffeine and it is still prescribed.

Caffeine can help to prevent and treat asthma symptoms. If we make observations, the coffee drinkers appear to have less asthma, but do not drink much, maximum three cups will do the good. It is also almost equal to a standard dose of theophylline.

If toxic level of theophylline is found in blood of the patients who take regular doses, we recommend strong coffee which can excrete theophilline very quickly from the body, thus preventing the toxic effects.

Three to four cups of strong black coffee is a good emergency treatment for an asthmatic attack which is as effective as theophylline.