Caffeine is a xanthine derivative — 1, 3, 7-trimethyl-xanthine. Other naturally occurring xanthines include the well-known theophylline (the major constituent in tea) and theobromine. Coffee is a major source of caffeine and chlorogenic acid and also contains a substantial amount of magnesium and other micronutrients. Caffeine is a powerful central nervous stimulant and moderate doses of 200 mg contained in two cups of coffee activate the cerebral cortex sufficiently to slow changes in an individ¬ual’s electroencephalogram (EEG). Caffeine is also a mild cardiac stimulant.
TABLE II Levels of Caffeine in Common Drugs
Standard Approximate mg
adult caffeine/standard
Drug dose dose
Prescription painkillers
Darvon compound capsule 1 32
Cafergot tablet (migraine) 1 100
Nonprescription (over-the-counter) painkillers
Anacin, Midol, Vanquish 2 65
Plain aspirin 2 0
Cold/allergy medicine
Dristan 2 30
Coryban-D, Sinarest, 1 30
Triaminicin
Stimulants
No-Doz 2 200
Vivarin 1 200
From Blount, J.P., and Cox, W.M. (1997), Caffeine, Encyclopedia of Human Biology, Vol. 2, 2nd Ed., San Diego: Academic Press, p. 275.