---
title: "Subconjunctival haemorrhage (red patch on the eye)"
description: "Why a bright red patch can appear on the white of the eye, why it usually looks worse than it is, and when to seek advice. Clinically reviewed."
url: https://eyehealthguide.org/conditions/subconjunctival-haemorrhage/
source: Eye Health Guide
licence: "General information only. Cite the URL and the named medical reviewer."
---

Condition

# Subconjunctival haemorrhage (red patch on the eye)

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

A subconjunctival haemorrhage is a bright red patch on the white of the eye caused by a tiny blood vessel bursting. It often looks alarming but is usually harmless and painless, and it clears on its own within one to two weeks without treatment.

### On this page ⌄

1. Your next step
2. What it is
3. Common symptoms
4. Causes and risk factors
5. When to seek care
6. Related conditions
7. Related symptoms
8. Frequently asked questions

## What it is

A subconjunctival haemorrhage happens when a small blood vessel just under the clear surface of the eye breaks, releasing blood that spreads into a flat red patch. It is common, usually harmless, and does not affect your vision.

## Common symptoms

There is usually little more than the appearance of the red patch.

- A bright red, flat patch on the white of the eye
- No pain or only mild awareness
- No change in vision
- Sometimes a mild scratchy feeling

## Causes and risk factors

It can follow coughing, sneezing, straining, vomiting, or rubbing the eye, and sometimes a minor injury. It is more common with age, with high blood pressure, or when taking blood-thinning medicines. Often no clear cause is found.

## When to seek care

Most need no treatment and clear within two weeks, gradually fading like a bruise. See a clinician if there is pain, changes in vision, it follows a significant eye injury, it keeps coming back, or it appears alongside easy bruising or bleeding elsewhere.

## Related conditions

## Related symptoms

## Frequently asked questions

### Is a subconjunctival haemorrhage dangerous?

It usually looks far worse than it is and is typically harmless, clearing on its own. Seek advice if it is painful, affects your vision, or follows an injury.

### How long does the red patch take to clear?

It usually fades over one to two weeks, changing colour like a bruise as it heals, and needs no treatment.

### What if it keeps happening?

Recurrent subconjunctival haemorrhages are worth discussing with a clinician, who may check your blood pressure or review any blood-thinning medicines.

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.

- [Moorfields Eye Hospital - Subconjunctival haemorrhage (PDF)](https://www.moorfields.nhs.uk/mediaLocal/bzyddglm/subconjunctival-haemorrhage.pdf)