Delusional Parasitosis

Delusional parasitosis is a syndrome in which the patient has the false belief that he is infested by some type of parasite. Although this is a psychiatric disorder, patients usually seek care from dermatologists. DP has various causes. It may occur as the sole psychologic disturbance, or it may be associated with an underlying psychiatric disorder or physical illness. A dermatology-psychiatry liaison is advocated for establishing a viable differential diagnosis and selecting appropriate therapy. The antipsychotic agent pimozide is currently the most effective treatment when DP occurs as an encapsulated delusion. Pimozide therapy requires careful monitoring because this drug has several potentially serious adverse effects, and relapse often occurs on discontinuation of the drug.

The symptoms of delusional parasitosis (a psychiatric disorder) are very similar to those presented by Morgellon sufferers who reject conventional diagnosis of their symptoms, and belief in the existence of parasites infested within them that cannot be observed except by the patients. There is no agreed upon differential diagnosis since Morgellons is not an accepted medical condition at the moment.