Occasionally a dentist is confronted with a painful, red facial swelling which has suddenly appeared, with no signs of a dental cause. In addition to the other possible causes, one should consider the possibility of an insect bite, especially in the summer months. The consequences of an insect bite or sting are often underestimated. Hymenopterae (wasps and honeybees) stings are not generally serious in nature, but can result in severe systemic medical complications, such as an allergic reaction. Dentists who are confronted with a patient with an insect bite or sting must provide the patient with adequate information and if necessary take measures in order to prevent further complications.