Life-threatening bite injury of the lower lip after use of metamizole

Introduction Bite wounds of the oral mucosa heal after eliminating the causative irritant, but there are serious exceptions from the rule. We present the case of a 37-year-old woman with an ulcer of the mucosa of the lower lip, which had been present for 10 days, and leucopenia.Discussion Agranulocytosis after the use of metamizole is part from leukaemia and lues, a rare reason for non-healing ulcers of the mucosa of the oral cavity without fulminant signs for inflammation.Conclusion As this is a life-threatening disease, medical therapy must begin immediately.