Infestatiewaan, een glasharde overtuiging

Delusional infestation is a rare psychiatric disorder, in which there is an unpersuadable erroneous belief that parasites, insects, worms or objects are infested in the skin without any medical evidence. It is of uttermost importance to differentiate between a primary or secondary type of delusional infestation. In a secondary delusional infestation symptoms are either the result of a somatic disease, another psychiatric disorder or symptoms are related to the use of medication or substances. Studies show that approximately a quarter of patients with delusional infestation used recreational drugs. In addition to medication, substance use in these patients should be evaluated, which can be easily done by a urinary test. We hereby present a case in which discontinuation of methylphenidate prescribed for ADHD (Attention Deficit Hyperactivity Disorder) resulted in the disappearance of the delusional infestation.