Antipsychotics in dermatology: Optimal choice of drugs for the treatment of delusional infestation and other potential uses for skin conditions

Delusional infestation (DI) is a psychiatric disorder defined by a fixed, false belief that one became infested by an organism without evidence to support this. Patients may report abnormal cutaneous sensations and present with excoriations, skin erosions, ulcerations and other skin lesions. In addition to a comprehensive history and detailed physical examination, laboratory workup should be considered depending on the clinical picture. DI can be categorized into primary or secondary. In primary DI, the patient has the delusion of being infested, but no other psychiatric or organic disorders are present. While the secondary forms of DI occur secondarily to other disorders such as psychiatric and organic diseases. Proper diagnostic workup for these patients is essential to rule out other explanations for symptoms and to investigate potential secondary causes of DI.¹ Antipsychotic medications are the most common drugs used in the management of patients with primary DI.²

Tang et al.³ performed a multicentre, retrospective observational study with patients diagnosed with DI using anonymized electronic patient records from two hospitals in the United Kingdom. These authors found that amisulpride and risperidone were associated with a higher treatment response than other antipsychotics, such as quetiapine, aripiprazole and olanzapine. According to this study, amisulpride and risperidone should be considered the first-line treatment options for patients with DI. This important study provides insight into the optimal choice of antipsychotics for patients experiencing this challenging condition. The use of antipsychotic drugs for other dermatological conditions has been investigated in the past years. Gupta et al.⁴ reviewed this topic and explained that these drugs can benefit dermatological patients due to their central nervous system and peripheral effects. They can be used as augmentation therapy of antidepressants, such as selective serotonin reuptake inhibitors (SSRI), for the management of trichotillomania (hair pulling disorder) and skin-picking disorder. Moreover, these drugs have a central postsynaptic dopamine D2 receptor-blocking effect with varying degrees of histamine H1 receptor, cholinergic muscarinic receptor and α1-adrenergic receptor-blocking effects, which could be potentially beneficial in the management of specific histamine or sympathetically mediated dermatological conditions. These drugs could have a potential role in treating other diseases, such as urticaria, pruritus and hyperhidrosis, but further research is warranted to confirm these benefits.

No conflict of interest with this paper content.