Charles Bonnet is a syndrome first described by the same-named naturalist and philosopher in 1769 after observing his grandfather, who suffered with the syndrome. It is characterized by the presence of complex, repetitive and persistent visual hallucinations that occurs in elderly people without cognitive impairment and with a significant visual loss associated. Its prevalence is estimated around 10-15% however it is believed to be underdiagnosed.

To describe, through the follow-up of a case report, the difficulties to make an accurate diagnosis of this syndrome and to select the most appropriate treatment.

A case report of a patient followed in an ambulatory mental health clinic.

Before the appearance of visual hallucinations in the elderly, the most frequent diagnosis suggested is cognitive impairment. Full, exhaustive neurological examination with visual field test, including pharmacological and medical history, as well as relevant additional tests help lead to correct diagnosis.

Interventions to reassure the patient, treat underlying visual disease and improve social factors allow symptom control.