theophylline
noun
the·oph·yl·line thē-ˈä-fə-lən 
: a feebly basic bitter crystalline compound C7H8N4O2 present in tea leaves that is isomeric with theobromine and is used in medicine especially as a bronchodilator
Example Sentences
Recent Examples on the Web And elderberry isn’t recommended for people taking diabetes medications, diuretics, corticosteroids, laxatives, the asthma drug theophylline, and those undergoing chemotherapy, Rothenberg adds. 
Erica Sweeney, Good Housekeeping, 27 Jan. 2021 When it’s broken down in the body, caffeine produces small amounts of the bronchodilator theophylline. Brad Rickman, Condé Nast Traveler, 17 Apr. 2018 The scientists found that amphetamine works with another ingredient, theophylline, a drug that is used for lung diseases such as asthma and bears a chemical resemblance to caffeine. Bradley J. Fikes, sandiegouniontribune.com, 16 Aug. 2017
Erica Sweeney, Good Housekeeping, 27 Jan. 2021 When it’s broken down in the body, caffeine produces small amounts of the bronchodilator theophylline. Brad Rickman, Condé Nast Traveler, 17 Apr. 2018 The scientists found that amphetamine works with another ingredient, theophylline, a drug that is used for lung diseases such as asthma and bears a chemical resemblance to caffeine. Bradley J. Fikes, sandiegouniontribune.com, 16 Aug. 2017 Word History
Etymology
International Scientific Vocabulary theo- (from New Latin thea tea) + phyll- + -ine entry 2
First Known Use
circa 1894, in the meaning defined above
Medical Definition
theophylline
noun
the·oph·yl·line thē-ˈäf-ə-lən
: a feebly basic bitter crystalline compound C7H8N4O2 that is present in small amounts in tea but is prepared chiefly by synthesis, that is isomeric with theobromine, and that is used in medicine often in the form of derivatives or in combination with other drugs especially as a bronchodilator to relieve or prevent symptoms of asthma and bronchospasm associated with chronic bronchitis and emphysema