A distribution study of CYP1A2 phenotypes among smokers and non-smokers in a cohort of healthy Caucasian volunteers

Objective: To analyse distributions of a urinary ratio of caffeine metabolites (MRc) representative of cytochrome P450 (CYP) 1A2 activity in a cohort of Caucasian German healthy volunteers and to re-assess the effects of smoking and oral contraceptives on the range and type of MRc distribution.