Objective. We searched the influence of dose and timing of atropine therapy in fenthion-induced pancreatitis model. Methods. All rats were intoxicated with fenthion except the control group. Two milligrams of atropine was administered for 24 hours in a high dose atropine group while a low dose atropine group received 100 micrograms of atropine for 24 hours. One group received 2 milligrams of atropine in the first four hours of intoxication while the other group received 2 milligrams of atropine in the last four hours before sacrifice. All rats were sacrificed 24 hours after intoxication. Pseudo-cholinesterase and lipase concentrations and histopathological markers of pancreatitis were studied. Results. None of the models in this study completely prevented pancreatitis, however high dose atropine that is administered for 24 hours or the first four hours after intoxication prevented severe pancreatitis. Conclusion. Atropine administration influence on fenthion-induced pancreatitis should be studied for other organophosphates in animals and humans.