Data Views Plants (>= 1 Chemical): 7 All Chemicals: 1 CSV Excel PDF Click on column headings to sort table by that column Chemical Dosage References THEOPHYLLINE --Pizzorno, J.E. and Murray, M.T. 1985. A Textbook of Natural Medicine. John Bastyr College Publications, Seattle, Washington (Looseleaf). *Unless otherwise noted all references are to Duke, James A. 1992. Handbook of phytochemical constituents of GRAS herbs and other economic plants. Boca Raton, FL. CRC Press.