Drug-induced Delusional Infestation.

It is considered that certain drugs might induce delusional infestation, yet, to date, no studies have been performed to identify the pharmacodynamics associated with these treatments. The aim of this review is to summarize current available knowledge of drug-induced delusional infestation. A literature search was performed for primary studies on suspected drugs reported to induce delusional infestation. Included articles were evaluated systematically using the Naranjo criteria. In addition, drug mechanisms of action were compared. The final selection included 31 studies, in which a total of 26 classes of drugs were identified. Anti-Parkinson drugs were most frequently associated with delusional infestation, followed by antidepressants, antiepileptics, antibiotics, prescription stimulants, and a few other drug groups. The current available literature suggests that the onset of delusional infestation is initiated by drug-induced alterations in neurotransmitter levels, predominantly dopamine, in the central nervous system.

Association Between Delusions of Infestation and Prescribed Narcotic and Stimulant Use.

OBJECTIVE: Patients diagnosed with delusions of infestation (DOI) at a psychodermatology clinic appeared to have a higher incidence of being prescribed narcotic or stimulant medications compared with the general dermatologic clinic population with chronic pruritic conditions. A retrospective study was conducted examining the correlation between patients with DOI and prescribed psychoactive medications. METHODS: Ninety-two patients with a diagnosis of DOI, seen at our University Psychodermatology Clinic, served as the study population. The comparison group (N=354) included dermatology patients seen at a dermatology clinic by the same dermatologist for itching, including adults seen for chronic pruritic conditions and contact dermatitis. For both groups, the reported use of any psychoactive prescription medications was noted. RESULTS: Patients with DOI were significantly more likely than other dermatology patients to receive prescriptions for narcotics [adjusted odds ratio (OR)=2.19; confidence interval (CI)=1.21-3.99) and stimulants (OR=5.44; CI=2.37-12.52). Patients with DOI were also more likely to be female (OR=2.49; CI=1.47-4.22) than patients who did not have such delusions. DISCUSSION: Few data are available concerning the etiology and management of DOI. Findings from this study indicated an association between the diagnosis of DOI and the prescribing of narcotics and stimulants, even when sex and age were taken into account. This information may be used to assist with the diagnosis of patients presenting with DOI and possible treatment options. It will be important to determine if these medications are a cause of the condition, or are merely correlated with other medical conditions.

Delusional infestation in the treatment of ADHD with atomoxetine.

The case describes an adult diagnosed with attention deficit hyperactivity disorder and treated with atomoxetine who quickly developed a florid case of delusional infestation. The patient described very distressing experiences that were significantly impacting her daily life. The symptoms improved with the withdrawal of atomoxetine and resolved completely with antipsychotic medications. Atomoxetine is proposed as the putative causative agent in this case.

[Ekbom syndrome in an intravenous methylphenidate abuser]. / Síndrome de Ekbom en consumidor de metilfenidato intravenoso.

Ekbom syndrome is a mental disorder in which the patient has the monothematic delusion of being infected by parasites. It is an uncommon condition that was initially studied by dermatologists. The exactly etiology is unknown to date, though several causes have been proposed, including metabolic diseases (among other physical causes), psychiatric disorders, drugs, etc. Research has now found a relationship between drug abuse and psychotic symptoms, which appear to be due to altered levels of dopamine at the receptor level. In this article we review the clinical features of the condition and present the case report of an intravenous methylphenidate abuser who developed a delusion of parasitosis.