Plasma concentrations, information and therapy adherence during long-term treatment with antidepressants.

The influence of information on drug plasma monitoring during long-term antidepressant therapy in fourteen ambulant, depressed patients was evaluated as variation in the L/D ratio time course. A larger variability in L/D ratio, with higher coefficient of variation and a poorer clinical outcome, was found in non-informed patients. The data support the hypothesis that verbal information on long-term drug monitoring of antidepressants could improve patients' adherence to therapy.