Amitriptyline, nortriptyline plasma levels and clinical response in women with affective disorders

The relationship between the plasma levels of amitriptyline and its metabolite nortriptyline, as well as their side-effects and clinical response, were studied in 102 depressed female in-patients, treated with different dosages of amitriptyline. For 50 and 100 mg dosages, significant positive correlations were found between amitriptyline concentration and the Hamilton amelioration scores, as well as between Hamilton final values and side effects. For depressive neurosis and involutional melancholia best therapeutic responses were yielded at a dosage of 50 mg, while in the treatment of manic-depressive illness, comparable results occurred at a 150 mg dosage. In the depressive neurosis and in the involutional melancholia the upper plasma concentration limits for the therapeutic effect of nortriptyline were identified. The lower plasma concentration limits of amitriptyline and nortriptyline in the treatment of manic-depressive illness were also pointed out.