Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women.
Article Details
- CitationCopy to clipboard
Pollock BG, Wylie M, Stack JA, Sorisio DA, Thompson DS, Kirshner MA, Folan MM, Condifer KA
Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women.
J Clin Pharmacol. 1999 Sep;39(9):936-40.
- PubMed ID
- 10471985 [ View in PubMed]
- Abstract
This study was conducted to investigate the effect of therapeutic estrogen on cytochrome P450 1A2-mediated metabolism in postmenopausal women using caffeine as a model substrate. Twelve healthy postmenopausal women underwent estrogen replacement therapy in the form of estradiol (Estrace). Estradiol was initiated at a dose of 0.5 mg a day and titrated to achieve a steady-state plasma concentration of 50 to 150 pg/ml. Caffeine metabolic ratios (CMR; paraxanthine/caffeine) were assessed both before and after 8 weeks of estrogen replacement. For the 12 subjects, there was a mean reduction in CMR of -29.2 +/- 25.0 (p = 0.0019). Consistent with previous results found in younger women, these results indicate that exogenous estrogen in older women may inhibit CYP1A2-mediated caffeine metabolism.
DrugBank Data that Cites this Article
- Drug Enzymes
Drug Enzyme Kind Organism Pharmacological Action Actions Estradiol Cytochrome P450 1A2 Protein Humans UnknownSubstrateInhibitorDetails Estradiol cypionate Cytochrome P450 1A2 Protein Humans UnknownSubstrateInhibitorDetails