Successful treatment of delusions of parasitosis with olanzapine

BACKGROUND: Delusional parasitosis is a rare disorder in which patients have a fixed, false belief of being infested with parasites. It is often accompanied by a refusal to seek psychiatric care. Delusions of parasitosis is classically treated with typical antipsychotic agents, the traditional dermatologic choice being pimozide. However, pimozide's adverse effect profile and the need for frequent electrocardiographic monitoring make such treatment less practical. OBSERVATION: We describe 3 patients who were diagnosed as having delusional parasitosis that was successfully treated with a recently Food and Drug Administration-approved atypical antipsychotic agent, olanzapine (5 mg/d). Olanzapine has a more benign adverse effect profile than typical antipsychotic agents and eliminates the need for electrocardiographic monitoring. Olanzapine therapy has been associated with such adverse effects as sedation, hyperlipidemia, weight gain, and insulin resistance, all of which were infrequent in our patients. CONCLUSION: Olanzapine is an atypical antipsychotic agent that can be used as a first-line agent in delusional parasitosis as a safer therapeutic option without a specialized monitoring regimen.     

Cocaine abuse and delusions of parasitosis

We report two persons in their thirties with the shared delusion of parasitosis. Both abused cocaine, and both recovered from their delusions after a period of abstinence. Although the literature does not stress that a specific cause is usually found for delusions of parasitosis, this may be changing for persons in groups among whom cocaine and possibly other illicit drug use is common. It is a service to these desperate patients to establish their confidence and then discretely ask about the use of illegal drugs, especially cocaine.     

Delusions of parasitosis and delusions of parasitosis by proxy in a mother and her children

Delusions of parasitosis by proxy is an uncommon entity wherein an individual projects a delusional belief onto another person who lacks capacity to hold the same belief. We report a case of delusions of parasitosis by proxy in a mother who believed that she was infested with scabies and projected her fixed, delusional belief of scabies infestation onto her children. She subjected her children to numerous home remedies and medical treatments as well as removing them from school in an effort to cure them of the supposed infestation. Child maltreatment can be a concern in such cases with a low threshold for involving child protective services if harm to the children is suspected.     

Treating patients with delusions of parasitosis: a blueprint for clinicians

Dermatologists often inquire how to approach a patient with delusions of parasitosis. Avoiding negative countertransference and developing a therapeutic alliance with the patient are key steps for dermatologists. Even though each case is unique, this article serves as a blueprint for clinicians on how to approach and treat these patients.     

Tales of bugs,delusions of parasitosis,and what to do

Delusions of parasitosis are usually a monosymptomatic dermatopsychiatric disorder manifested by the fixed false belief that insects are crawling over the body producing an intractable itch. Also known as parasitophobia, this disease can also be associated with other psychiatric disorders, such as schizophrenia or obsessive compulsive disorders. In most cases, the delusion is encapsulated and other mental functions remain intact. Parasitophobia is usually seen in middle-aged women and has proven a vexing problem for dermatologists to treat because patients are often reluctant to obtain a psychiatric consultation and wary of taking antipsychotic or antidepressant medication. Four patients with this disorder illustrate the problem, provide a new approach to understanding the precipitating factors in the onset of the disease, and permit the introduction of a previously undescribed therapy, escitalopram (Lexapro, Forest Pharmaceuticals, New York, NY), a selective serotonin reuptake inhibitor with less side effects than the previously favored therapy with pimozide.     

A review of delusions of parasitosis, part 1: presentation and diagnosis

Delusions of parasitosis (DOP), a psychiatric disorder in which patients erroneously insist that they are infested with parasites, remains a fascinating entity with elusive origins. Typically, these patients are resistant to psychiatric referral and treatment with psychotropic medications. We discuss the classification, epidemiology, clinical presentation, etiology, associated features, and differential diagnosis of this disorder. The authors reviewed case reports and clinical trials and tabulated the epidemiologic data, which show DOP is more common than previously thought.     

An approach to the treatment of psychogenic parasitosis

Background Patients with psychogenic parasitosis typically seek help from nonpsychiatric physicians and can be difficult and time-consuming to treat. Pimozide has been promoted as the treatment of choice but is not indicated for every patient presenting with this symptom. Our purpose was to develop a realistic treatment protocol for the nonpsychiatric physician faced with these patients.
Methods Using what is known about this problem through review of the literature and our own experience with 20 patients, a practical treatment strategy is suggested.
Results It is proposed that dermatologists and primary care professionals seeing these patients determine (1) whether or not the patient's belief in infestation is shakable and (2) whether or not the patient is depressed, in order to chose a therapeutic plan.
Conclusions Dermatologists and psychiatrists can work together to develop treatment protocols that minimize risk and maximize therapy for patients with psychogenic parasitosis.     

Successful treatment with pimozide of delusional parasitosis

An introduction to the concept of delusional parasitosis is presented. The persistent and refractory nature of the condition is emphasized. A case history is described in which a 67-year-old spinster, with classical symptoms of this condition, responded extremely favourably to simply administered pharmacotherapy. The authors allude to five similar patients also treated successfully by the same method. It is suggested that dermatologists might profitably treat this condition without recourse to psychiatric referral, which can often be counter-productive.     

Psychological interventions in the treatment of delusional parasitosis: a brief review

This review synthesized evidence on the most up-to-date treatment outcomes in patients with delusional parasitosis and examined the impact of incorporating psychological interventions in conjunction with psychiatric treatment. The reporting of this review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. PubMed and Google Scholar were searched between 2013 and 2023. Nine studies were included in this review. Partial remission was observed across all cases, irrespective of the treatment approach employed. Complete remission was limited to only three studies. No correlation was observed between the incorporation of psychological intervention in conjunction with psychotropic medication and an enhanced remission outcome. The findings underscore the importance of psychotropic medication as a fundamental component in the treatment of delusional parasitosis. The results highlight that although first- and second-generation psychotropic medications are the mainstay treatment options, they nevertheless play a limited role because of the patients' steadfast delusions of infestations.     

Delusions of parasitosis

ABSTRACT:  Delusions of parasitosis is a rare psychiatric disorder in which the patient has a fixed, false belief that he or she is infested by parasites. Even though it is a psychiatric disorder, these patients usually present to a dermatologist because they are convinced that they have a dermatologic problem. Patients with delusions of parasitosis generally reject psychiatric referral. The traditional treatment of choice for delusions of parasitosis is the antipsychotic medication pimozide (Orap, Gate Pharmaceuticals, Philadelphia, PA). The use of pimozide has been limited by its adverse effects, most notably extrapyramidal adverse effects. There is now an emerging role for atypical antipsychotics with a safer adverse effect profile in the treatment of delusions of parasitosis. However, the most challenging aspect of managing these patients may be the challenge of establishing rapport in the face of unshakable delusional ideation.