Desmethyldiazepam levels were higher in Asian Americans than Caucasians. The free fraction of diazepam was identical in both groups (0.02). Volume of distribution at steady state (Vdss) was different when calculated as absolute volume Vdss = 76.55 (+/- 9.63) in Caucasians and 54.96 (+/- 4.55) in Asian Americans (p = 0.04) and marginally significant when corrected for body weight Vdssl/kg = 1.10 (+/- 0.11) in Caucasian and 0.88 (+/- 0.05) in Asian Americans, (p = 0.07). Total body clearance, but not elimination half-life, was higher in Caucasians compared to Asian Americans.
(N = 25; Caucasians (n=12) and Orientals (Asian Americans, n=13)), Ghoneim, 1981.