Successful Ziprasidone Monotherapy in a Case of Delusional Parasitosis: A One-Year Followup

Delusional parasitosis is characterized by the false idea that own body is infested by invisible mites, insects, or other parasites. This case report describes a 24-year-old woman with delusional parasitosis who was treated with ziprasidone monotherapy (120？mg/day) with a complete remission of delusion and followed for one year without symptom recurrences. These findings, although preliminary, indicate that further investigation of ziprasidone monotherapy for the treatment of delusional parasitosis is warranted in further trials. 1. Introduction Delusional parasitosis (also known as Ekbom syndrome, delusion of infestation, psychogenic parasitosis, dermatozoenwahn, and dermatozoic delusion) is characterized by the idea that own body is infested by invisible mites, insects, or other parasites [1]. Patients often complain about itching that attribute to the existence of such animals in or under the skin [2]. It is mainly considered a monosymptomatic hypochondriacal psychosis meeting DSM-IV-TR criteria for delusional disorder, somatic type [3], but it may also be associated with other psychiatric or organic diseases [4, 5]. In fact, it should be noted that the diagnosis of primary delusional parasitosis may be suggested only after real parasite infections or other underlying medical or psychiatric comorbid conditions have been ruled out, as delusional parasitosis may be often associated with some physical illnesses, several psychiatric disorders, or substance abuse/intoxications [1, 2, 6]. It has also been reported that delusional parasitosis can also occur as a shared psychotic disorder (folie à deux or folie à trois) and even as by proxy [7]. The patients with untreated primary delusional parasitosis may be at risk of committing suicide [8]. Both typical and atypical antipsychotics have been successfully employed in the treatment of primary delusional parasitosis [9–11] and many sources have recommended the use of the typical antipsychotic pimozide, that seems particularly effective. Contreras-Ferrer et al. [12] described the case of a 73-year-old patient with delusional parasitosis who did not responded completely to pimozide and was successfully treated with ziprasidone augmentation. However, to date, no information is present on efficacy of ziprasidone monotherapy in the treatment of primary delusional parasitosis. 2. Case Report The case was a 24-year-old female university student who came to our observation at our outpatient facility in December 2010, after several consultations at the emergency unit of our hospital. She complained that an unknown