Symptoms as predictors of response to amitriptyline and nortriptyline -- the plasma level variable

Data collected to define therapeutic plasma levels for amitriptyline and nortriptyline were re-analyzed to test endogenous and non-endogenous symptoms as response predictors while controlling for plasma level variable. The selection criteria limited the range of historical predictors. Initial symptom quality was not predictive of outcome for the entire group of 44 patients or for the 27 with therapeutic plasma levels. Delusions were not associated with poor outcome. The authors conclude that historical components of the endogenous--non-endogenous distinction (e.g., premorbid personality, stability of symptoms over time, quality of remissions) may be more important as response predictors.