Effect of age and gender on citalopram and desmethylcitalopram steady-state plasma concentrations in adults and elderly depressed patients.

The effect of aging on steady-state plasma concentrations of citalopram (CIT) and desmethylcitalopram (DCIT) was investigated in 128 depressive patients treated with 10-80 mg/day CIT. They were separated into three groups, with age up to 64 years (mean age+/-S.D.

Effects of grapefruit juice on the pharmacokinetics of the enantiomers of methadone.

Background And Objectives: Cytochrome P450 (CYP) 3A4 is the main CYP isozyme involved in methadone metabolism. We investigated the influence of grapefruit juice, which contains inhibitors of intestinal CYP3A, on the steady-state pharmacokinetics of methadone.

Methods: For 5 days, 8 patients undergoing methadone maintenance treatment received 200 mL water or grapefruit juice 30 minutes before and again together with their daily dose of methadone.