Cannabis use in delusional infestation with folie à deux

ABSTRACT

Introduction

Delusional infestation (DI) occurs when individuals falsely believe their skin or body is infested with insects or parasites, and is sometimes associated with shared psychotic disorders. Previous studies show substance use is common in individuals with DI, but few have investigated which drugs are most often associated.

Methods

A 65-year-old male with 42 years of recreational cannabis use was admitted medically for progressive weakness and abdominal pain. He stated his symptoms were a reaction to holistic remedies he and his wife used to self-treat parasite infections. Both endorsed mites invading their bodies. Concurrently, the patient’s wife, a 71-year-old female with medical cannabis use, presented to the hospital portraying a similar story.

Results

While the male patient was discharged home, the female patient was psychiatrically hospitalized. Risperidone improved her somatic complaints and overall functioning.

Discussion

These cases highlight the potential role of cannabis use in DI and shared psychotic disorders. Research has linked dopaminergic agents to the development of DI. Considering elevated rates of cannabis use in the psychiatric population, further studies should investigate the link between such and DI, including shared delusional disorders.

Conclusion

Physicians should be knowledgeable of the association between DI, shared delusional disorder, and cannabis use.

KEYWORDS:

• Delusional infestation
• delusional parasitosis
• marijuana
• cannabis
• folie a deux

Disclosure statement

On behalf of all authors, the corresponding author states that there is no conflict of interest.