Can diphenhydramine prevent organophosphate-induced acute pancreatitis? An experimental study in rats

Acute pancreatitis (AP) is a well known complication of organophosphate (OP) poisoning and the true incidence is unknown; but, may be more common than clinically suspected. Previous studies suggest that Diphenhydramine (DPH) may be useful as an alternative or adjunctive therapy in OP poisoning. The aim of this experimental study was to investigate whether DPH could prevent or diminish pancreatic damage caused by OP poisoning as defined by histologic findings, and serum interleukin 10 (IL-10) and tumor necrosis factor alpha (TNF-α) levels. Twenty-four Sprague- Dawley rats were divided into equal three groups. Group 1 did not receive any agent during the experiment. Group 2 received 0.8 g/kg fenthion subcutaneously followed by 3 ml/kg normal saline intramuscularly, 30 min later. Group 3 received 0.8 g/kg fenthion subcutaneously, followed by 30 mg/kg DPH intramuscularly, 30 min later. Twenty-four hours later, pancreatic tissues were excised and blood samples were taken. After blood samples were taken by cardiac puncture, the animals were sacrificed. Treatment with DPH significantly decreased the serum TNF-α and increased the serum IL-10 levels. DPH significantly reduced pancreatic damage, including edema, inflammation, vacuolization and necrosis, as determined by pathologic scoring. The present study show that DPH decreased the severity of OP induced AP in rats. This effects may be related to a decrease of TNF-α level and increase of IL-10 level.