What is a black eye?

A black eye is a bruise in the tissues around the eye. Depending on how it happened, it may be a good idea to get it checked out by a doctor in case you have a more serious injury. A black eye is also known as periorbital haematoma.

A black eye develops when fluids collect in the tissues around the eye. The bruising and blue and purple discolouration are caused by broken blood vessels under the skin. These tissues will usually be swollen too. The eye itself is not usually damaged.

A black eye can often look worse than it actually is. That’s because the skin around the eye is quite loose, thin and transparent, meaning it puffs up easily and even a little pooling of blood can cause discolouration.

Sometimes you might also have bleeding inside your eye, and this is a medical emergency that needs treatment. Alternatively, the white of your eye might be bright red because there is bleeding on the surface of the eye. This is not usually serious.

After a few days, the black and blue bruises will fade to yellow or green as the blood is reabsorbed into the body. Black eyes usually take up to 2 weeks to heal.

What causes a black eye?

The most common cause of a black eye is a knock to the area, causing trauma, following an accident, assault, contact during sport or even if you just walk into something.

Other causes of a black eye include:

• dental work or surgery (for example, cosmetic surgery or nasal surgery)
• sinus infection or an infection around the eyes
• a skull fracture (usually causing a black eye in both eyes)
• an allergic reaction or some other health condition
• assault

When should I see my doctor?

See a doctor if the eye becomes infected or has not healed after 2 weeks.

You should seek medical help right away if you lost consciousness when you received the black eye.

You should also seek immediate medical help if you have these symptoms along with the injury:

• loss of vision or visual changes (other than blurriness caused by the swelling)
• severe eye pain or headaches that don't go away
• bleeding from the eye, or blood on the eyeball's surface or inside the eye
• trouble breathing through your nose
• nausea, vomiting, dizziness or lethargy
• memory lapses

How is a black eye treated?

Black eyes normally get better by themselves. If you have one, place a cold compress, such as a bag of frozen peas, over the area as soon as possible. Keep it in place for 15 to 20 minutes at a time, every hour while awake, for the first 24 hours. This will limit the swelling.

If you see a doctor, they will examine you and may order tests to make sure there are no fractures or other problems.

You can take over-the-counter medicines to help with pain relief. Avoid aspirin, unless you are normally taking it regularly for other reasons, since this thins the blood and could make the bruising worse. Never put a steak on a black eye because this increases the risk of infection.

Black eye self-help

A few days after you receive the black eye, you can speed up the healing by swapping the cold compresses for a warm — but not hot — compress. This increases blood flow to the area. Massage gently around the eye area, but not the eye itself.

Protect the injured eye by avoiding sports or any other activity that could cause you to hit the eye.

Can a black eye be prevented?

If you do the kind of work that could injure your eyes, ensure you use suitable protection at work as well as when doing household DIY. For example, use safety glasses where appropriate. Make sure you have the skills required during sport and use appropriate protective eyewear if you need to.