Two prospective dosing methods for nortriptyline.
This study compared two prospective pharmacokinetic dosing methods to predict steady-state concentrations of nortriptyline. One method required multiple determinations of the nortriptyline plasma concentration to estimate the drug's steady-state concentration. The second method required a single nortriptyline concentration drawn at a fixed time, preferably 36 hours, following a nortriptyline test dose. The 36-hour nortriptyline plasma concentrations (NTP 36h) were substituted into the straight-line equation of Cssav = 17.2 + 3.74 (NTP 36h), where Cssav is the average steady-state concentration for a 100 mg/day dose of nortriptyline. No differences were noted between the observed steady-state nortriptyline concentration of 121 +/- 19 ng/ml, the 36-hour single-point prediction mean concentration of 121 +/- 21 ng/ml, or the multiple-point prediction mean concentration of 122 +/- 19 ng/ml. Because of the similar findings between the two methods, the clinical advantages and disadvantages of each kinetic approach are discussed to put these prospective dosing protocols into their proper perspective.
D000328:Adult; D000368:Aged; D005260:Female; D006207:Half-Life; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009661:Nortriptyline / Q000008:administration & dosage* / Q000097:blood / Q000627:therapeutic use
D009661:Nortriptyline