---
title: "Charles Bonnet syndrome | Eye Health Guide"
description: "What Charles Bonnet syndrome is, why people with poor vision may see images that are not real, and how it differs from dementia or psychosis."
url: https://eyehealthguide.org/conditions/charles-bonnet-syndrome/
source: Eye Health Guide
licence: "General information only. Cite the URL and the named medical reviewer."
---

Condition

# Charles Bonnet syndrome

Medical reviewer [Mr Mohamed Mohyudin](https://eyehealthguide.org/reviewers/mohamed-mohyudin/)· Last recorded site review July 6, 2026

### About this review

This page inherits the site’s previous review record. A separate, current article sign-off has not yet been recorded.

[How review works](https://eyehealthguide.org/reviewers/) · [Official biography & credentials](https://mohamedmohyudin.co.uk/author/mohamed-mohyudin/)

Quick answer

Charles Bonnet syndrome causes vivid visual hallucinations in people who have lost a significant amount of sight, usually in older adults with conditions such as macular degeneration or glaucoma. The images can be people, animals, patterns or whole scenes. Insight is usually preserved — people know the images are not real. It is not dementia or psychosis, but it can be frightening and deserves explanation and support.

### On this page ⌄

1. Your next step
2. What it is
3. Common features
4. Causes and links
5. What helps
6. Related conditions
7. Practical guides
8. Frequently asked questions

## What it is

When the brain receives less visual input from damaged eyes, it may fill in missing information with spontaneous images. This is similar to phantom limb sensations after amputation. Charles Bonnet syndrome is surprisingly common in people with severe sight loss but is often under-recognised.

## Common features

Hallucinations are only visual — there are no voices or beliefs that others cannot see.

- Seeing people, animals, faces or patterns that are not there
- Images may be still or moving, black-and-white or coloured
- Usually no interaction with the hallucination
- Person understands the images are not real
- Often worse in low light, quiet periods or when alone

## Causes and links

It is linked to significant vision loss from any cause, including macular degeneration, glaucoma, diabetic eye disease, stroke affecting vision, or cataracts before surgery. Better lighting, social contact and treating eye disease where possible may reduce episodes.

## What helps

Explaining the condition often reduces fear. Eye movement, brighter lighting, distraction, and talking to family or low-vision services help many people. If hallucinations are distressing or insight is lost, medical review is needed to exclude other causes.

## Related conditions

## Practical guides

## Frequently asked questions

### Is Charles Bonnet syndrome a sign of dementia?

Usually no. People typically know the images are not real and have no other hallucinations or confusion. However, if insight is lost or behaviour changes, medical review is important.

### What triggers visual hallucinations in poor sight?

Reduced visual input to the brain is the main trigger. Episodes may be worse in dim light, at rest, or after recent vision loss.

### Can Charles Bonnet syndrome be treated?

There is no single cure, but explaining the condition, improving lighting, treating reversible eye disease, and low-vision support reduce distress. Specialist advice helps if episodes are frequent or frightening.

Your next step

## Take this to your appointment

Write down what has changed, when it started, your current medicines and the questions you want answered. Take these to your eye-care appointment.

Sudden loss of sight, severe eye pain or a dark curtain across vision needs immediate assessment. Do not wait to complete a worksheet.

## Sources for this information

These references support the information on this page. Follow the linked source for its full context.

- [NHS - Charles Bonnet syndrome](https://www.nhs.uk/conditions/charles-bonnet-syndrome/)