Evaluation of tolerance in long-term treatment of cancer pain with epidural morphine.Int J Clin Pharmacol Ther Toxicol. 1983 Nov; 21(11):587-90.IJ
The effect of epidural morphine as a pain reliever was evaluated. A catheter was placed in the epidural space in 43 patients suffering from cancer pain related to dermatomeres of the thorax and lumbosacral region for an average period of 38 days (range 3-257 days). The daily dose of morphine hydrochloride varied from 1 to 5 mg with an average dose of 4.23 (+/- 2.4) mg. The treatment was divided into 10-day periods and for each of these periods the average daily dose relative to the total number of cases was calculated. The results showed no significant increase of the dose of epidural morphine in the first 10 decade periods. The authors concluded that pain relief treatment with equal doses maintains its effect for quite a long period of time in patients with often limited life expectancy.