This is a case report of a 63-year-old patient with no previous attentions in mental health. He is referred by his general practitioner because he presents wounds all over his body. He reports that there is a plague of bugs at his place that bite him everywhere. Therefore, he scratches continuously, trying to remove the stingers, and injuring himself all over. The family ensures there are no bugs at all, but the patient threatens to set fire to the house in order to extinguish the plague or even kill himself. An OCD with cleaning compulsive behavior was also present since many years, as well as an alcohol abuse. The patient required hospitalization in the psychiatry service. Organic cause for the disorder was discarded. Long-acting injectable aripiprazol was introduced and the patient stopped drinking. Progressively, the delusional symptoms began to subside. Now he maintains no awareness of illness but he says the bugs are disappearing and, at least, they do not bite him anymore.