Imagine that: cholinesterase inhibitor treatment of complex visual hallucinations of unknown aetiology

ABSTRACT

Introduction: Our objective is to highlight the value of the neurophenomenological classification of complex visual hallucinations (VHs). This approach enabled the authors to successfully treat VHs of uncertain aetiology with cholinesterase inhibitors because the content of the hallucinations suggested dysfunction in cholinergic modulated networks.

Methods: We utilise the single case report to describe the nature and content of chronic VHs experienced by a 49-year-old woman following a prolonged admission to ITU. Despite extensive investigation, no clear cause was identified for these hallucinations and the patient did not respond to rationalisation of medications or trials of antipsychotics. We therefore adopted the neurophenomenological approach to classifying and treating her VHs.

Results: After several years of distressing visual hallucinations, a course of Rivastigmine was trialed despite no evidence suggestive of a Parkinsonian syndrome. Nevertheless, the patient reported a dose-effect response with significant reduction in the frequency and intensity of her hallucinations, almost to complete resolution.

Conclusions: At present there is limited evidence about the medical management of visual hallucinations. This case report suggests that cholinesterase inhibitors may be of benefit, even in the absence of clear parkinsonsian features, if the form and content of the VHs suggest dysfunction in cholinergic modulated attentional networks.

KEYWORDS:

• Visual hallucinations
• cholinergic system
• rivastigmine

Disclosure statement

No potential conflict of interest was reported by the author(s).

Notes

1 Although we note here the ongoing debate about the psychopathological nature of Anton’s syndrome which Anton himself declared a delusion, some view as hallucinatory, while the more modern approach has been to consider it a special sort of confabulation (Hirstein, 2009).

Additional information

Notes on contributors

Y. Salih

Dr Y. Salih is an FY2 interested in acute medicine and ITU.

A. De Angelis

Dr A. De Angelis is a neuropsychiatrist with a special interest in movement disorders.

N. A. Poole

Dr N. A. Poole is a consultant neuropsychiatrist with an interest in models of psychopathology.