Role of Oxygen-Derived Free Radical Scavengers in the Treatment of Recurrent Pain Produced by Chronic Pancreatitis

Abstract

This randomized double-blind trial examined the influence of the radical scavengers allopurinol (50 mg per rectum, four times per day) and dimethyl sulfoxide (500 mg per rectum, four times per day) on pancreatic pain treated with intramuscular pethidine hydrochloride (100 mg followed by 50 mg every 4 hours until complete pain relief) in patients given nothing orally and intravenously hydrated. Addition of allopurinol or dimethyl sulfoxide to the analgesic regimen significantly enhanced its efficacy, enabling at least 57% (13 patients receiving allopurinol and 12 patients receiving dimethyl sulfoxide) of 43 patients to be free of pain within 12 hours after admission compared with only four (17%) of 23 controls achieving the same effect. This advantage extended to all patients within 24 hours after admission, leaving 11 controls (48%) still in pain. Consequently, all patients given allopurinol or dimethyl sulfoxide were discharged 3 days after admission, a result realized in only five (22%) of the assessable controls who were discharged after 5 days of hospitalization. The results suggest that oxygen-derived free radicals are implicated in the mechanism of abdominal pain caused by alcohol-induced chronic pancreatitis and that removing them results in a beneficial therapeutic effect.