Mirtazapine is NOT Recommended for Charles Bonnet Syndrome
Mirtazapine should not be used to treat Charles Bonnet Syndrome (CBS), as there is no significant evidence supporting pharmacological treatment efficacy for this condition, and the primary management approach is patient education and reassurance. 1
Evidence-Based Management Approach for CBS
First-Line Management: Education and Reassurance
Patient and family education is the cornerstone of CBS management, as discussion often leads to significant relief and decreased anxiety once patients understand the benign nature of their hallucinations. 1
Patients should be reassured that CBS hallucinations are a common cortical-release phenomenon resulting from lack of afferent visual information, not a sign of psychiatric illness or dementia. 1
Non-Pharmacological Interventions
Self-management techniques should be recommended first, including eye movements, changing lighting conditions, or distraction methods, as limited case series evidence suggests these may reduce hallucinations in some patients. 1
Vision rehabilitation referral should be considered to optimize remaining visual function and provide additional support. 1
Pharmacological Treatment: Limited Evidence
Although various pharmacological treatments are reported in case reports, there is currently no significant evidence of efficacy for any medication in CBS. 1
While mirtazapine is mentioned in palliative care guidelines for insomnia (7.5-30 mg at bedtime), this indication is unrelated to CBS and does not support its use for visual hallucinations. 1
Case reports have described potential benefit from SSRIs (venlafaxine, escitalopram) for CBS hallucinations, but these represent low-quality evidence from individual cases or small series, not guideline-level recommendations. 2, 3
Critical Diagnostic Considerations
Confirm CBS Diagnosis Before Any Treatment
- Verify all four diagnostic criteria are present: recurrent vivid visual hallucinations, intact insight that hallucinations are unreal, no other neurological/medical explanation, and documented vision loss. 1, 4
Red Flags Requiring Alternative Diagnosis
Atypical features mandate medical or neuropsychiatric evaluation, including: lack of insight despite CBS explanation, hallucinations that interact with the patient, or associated neurological signs/symptoms. 1
Other conditions causing hallucinations must be excluded: Parkinson's disease, dementia with Lewy bodies, Alzheimer's disease, psychiatric disorders, or medication side effects. 1, 4
Comprehensive workup should include neuroimaging (preferably MRI), medication review (especially anticholinergics, steroids, dopaminergic agents), and cognitive assessment. 4
Clinical Pitfalls to Avoid
Do not prescribe antipsychotics for CBS, as they are often ineffective and carry significant risks in elderly patients with vision impairment. 3
Do not assume hallucinations require medication—most CBS patients need only education and reassurance about the benign nature of their symptoms. 1, 5
Do not overlook treatable vision conditions—optimizing visual acuity through cataract surgery or other ophthalmologic interventions may reduce hallucination frequency. 5