Prediction of individual dosage of nortriptyline in depressed elderly outpatients.
Individual daily dosages of nortriptyline (NT) can be predicted from administration of a 50-mg or 100-mg single test dose, with a determination of the plasma level 24 hours later. Because the 50-mg or 100-mg test dose used in previous studies may cause unmanageable acute side effects in elderly patients, a 25-mg NT test dose was used to establish a 24-hour plasma level in 18 physically healthy, moderately depressed, geriatric outpatients. Correlations between the 24-hour test dose plasma level and steady state levels were done for maintenance dosages of 50, 75, and 100 mg/day. A nomogram was made from the regression equations to predict the dosage required to achieve a steady state concentration within a 50 to 150 ng/ml range. The importance of the ability to predict NT dosage requirements in geriatric patients is indicated by findings that at daily NT doses of 50 and 100 mg, nearly one-half of subjects had steady state levels below or above 50 or 150 ng/ml, respectively.
Schneider
L S
LS
Department of Psychiatry and the Behavioral Sciences, University of Southern California School of Medicine, Los Angeles 90033.
Cooper
T B
TB
Staples
F R
FR
Sloane
R B
RB
D000368:Aged; D000369:Aged, 80 and over; D003866:Depressive Disorder / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008875:Middle Aged; D009661:Nortriptyline / Q000008:administration & dosage* / Q000097:blood
D009661:Nortriptyline