Blood pressure response to the "second cup of coffee".
Twenty young male coffee-drinkers consumed 150 mg of caffeine in decaffeinated coffee three times a day for 8 days. On days 3, 4, 7, and 8, caffeine or a placebo was administered in the laboratory at 11 A.M., 8 A.M., 11 A.M., and 8 A.M., respectively, in a randomized double-blind crossover design. There was a blood pressure increase relative to the placebo 45 min after taking caffeine at 8 A.M. (5.8/6.5 mm Hg). An increase of 2.4/5.2 mm Hg was seen with the second cup of coffee at 11 A.M. The lower the subject's pre-coffee serum caffeine level, the higher the systolic response, both at 8 A.M. (r = -0.60) and at 11 A.M. (r = -0.62). Because of the pressor effect resulting from habitual caffeine intake, the adverse implications of caffeine use should be considered.
Goldstein
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IB
Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles 90024-1759.
Shapiro
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D
Hui
K K
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Yu
J L
JL
D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D002110:Caffeine / Q000008:administration & dosage*; D003069:Coffee; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D016032:Randomized Controlled Trials as Topic
D003069:Coffee; D002110:Caffeine