Abstract
Attention-deficit hyperactivity disorder (ADHD) is generally treated with stimulant medications without significant complications. Delusional parasitosis (Ekbom syndrome) can occur secondary to ADHD treatment. It is a rare condition defined as having a fixed, false belief that one is infected with insects, parasites, or organisms and that one experiences cutaneous sensations without any clinical evidence of infestation. Although stimulant treatment with methylphenidate or mixed amphetamine salts has been associated with delusional parasitosis, there is yet a case in the literature illustrating delusional infestation secondary to lisdexamfetamine. The following case is unique in that lisdexamfetamine caused delusional parasitosis in a 53-year-old man with ADHD who previously tolerated mixed amphetamine salts and armodafinil without side effects. The discontinuation of lisdexamfetamine, coupled with a second-generation antipsychotic, quickly resolved the delusion. For those who may prescribe lisdexamfetamine or treat patients with ADHD, it is crucial to carefully assess medication use, as discontinuation or dose adjustment of the suspected causative drug can have a positive impact on the course of delusional parasitosis.