[Treatment chronic pain with amitriptyline. A double-blind dosage study with determination of serum levels]

The aim of this study was to find an optimal analgesic dose of amitriptyline, and at the same time examine whether a therapeutic window existed for this analgesic effect. 85 patients with chronic, non-malignant pain were included in a double-blind treatment regime with four doses of amitriptyline (10, 25, 50 or 100 mg). A blood sample was taken at steady state. The results showed 25 mg amitriptyline to have a good analgesic and sleep regulatory effect. The four different doses of amitriptyline did not show any significant difference in efficacy. No therapeutic window was found, but one cannot exclude that it exists. Low-dose amitriptyline, as a non-addictive drug, is a good alternative in the treatment of chronic pain, independent of co-morbid depression.