Estimating steady state desipramine levels in noninstitutionalized elderly patients using single dose disposition...

Clearances calculated from single oral dose data have been utilized to predict steady state levels of desipramine in 12 noninstitutionalized depressed elderly patients. Observed steady state plasma levels correlated very well (r = 0.967, p less than 0.0005) with those predicted from single dose clearances, but not with plasma levels obtained 20 hours after a single oral dose (r = 0.24, p greater than 0.2). The mean half-life of desipramine (20.9 hours) in this group of elderly (mean age, 72 years) was considerably less than values of "apparent disappearance" half-life previously reported for elderly patients receiving imipramine. The single dose clearance technique yielded a precise criterion for quantitating early compliance with and adjusting drug dosing regimens.