Patient information from BMJ

Bell's palsy

Last published:Nov 30, 2023

If you suddenly find that your face droops on one side, you may have Bell's palsy. This can be alarming, but Bell’s palsy usually causes temporary muscle weakness and most people recover completely.

What is Bell’s palsy?

If you have Bell's palsy the muscles of your face suddenly become weak. This happens when a nerve sending messages from your brain to the muscles of your face stops working properly. It almost always happens on just one side of the face.

We don't know for certain what causes Bell's palsy. It may be due to swelling around the nerve, caused by a virus.

Not everyone who has weak face muscles has Bell's palsy. Some people with similar symptoms have another condition, such as an ear disease, a stroke, or the weakness may be due to an injury. If you have a stroke, other parts of your body are usually affected too.

You won't be diagnosed with Bell's palsy until other problems have been ruled out. You may need tests such as an MRI scan or a CT scan to rule out conditions other than Bell's palsy. In some cases, you may also need nerve tests to see if the nerve is working properly.

What are the symptoms?

You might find that your face droops on one side and it's hard to close or open one eye. You may not be able to frown or smile properly and your speech may be slurred. Having less control over your mouth muscles might mean that you dribble saliva.

Some people get ear pain or an ache behind the ear for a few days. Bell's palsy isn't usually painful, but you may find loud noises unpleasant. You may also lose your sense of taste on the affected side of your tongue.

These symptoms come on quickly and may get worse over 2 to 3 days.

Bell's palsy only affects the face. If you feel weak or numb in other parts of your body you should tell your doctor immediately.

What treatments work?

Most people recover from Bell's palsy within about 6 months, even without treatment. But treatment can help relieve the symptoms and help you recover more quickly.

Medicines

The main treatment for Bell's palsy is steroid tablets known as corticosteroids. They work by reducing the inflammation (swelling) around the affected nerve. Corticosteroids seem to work best if you take them within 3 days of your symptoms starting. You'll probably need to take the tablets for 10 days.

Taking steroids for a long time at a high dose can cause side effects. But the short courses of steroids used to treat Bell's palsy are unlikely to cause these problems.

Doctors sometimes prescribe antiviral tablets alongside steroids. Antiviral tablets attack the virus that may be causing the problem. Antiviral drugs might help when used together with steroids, but they don't help when used on their own.

Eye protection

Many people with Bell's palsy find that they can't properly close the eye on the affected side of the face. This means that there is a danger the eye could become too dry, which could cause permanent damage.

There are several things you can do to avoid this.

• Wear glasses or sunglasses during the day to protect the eye.

• Use eye drops called artificial tears to keep the eye moist.

• Use a lubricant ointment on the affected eye and tape it closed while you sleep.

If your doctor has concerns about your eye health, they may refer you to an ophthalmologist (eye doctor).

Surgery

Surgery for Bell's palsy can help people to recover. But it is a complex operation only used for people with severe symptoms.

The operation involves removing part of the bone in the face. This gives the affected nerve room to swell without causing other problems.

What will happen to me?

You have a good chance of recovering completely from Bell's palsy. This means that you will regain all or most of the muscle control in your face. But about 3 in 10 people will be left with some muscle weakness.[1]​

Some people may also experience long-term problems that cause unwanted movements in the face. This is called synkinesis, but it is not common.

You're more likely to have long-term problems if:

• You have no movement at all in the affected side of your face

• You are an older adult

• You have diabetes, or you're pregnant

• You haven't started to recover after 6 weeks.

Bell’s palsy can be distressing. You may find counselling helps you cope with these changes.

Very few people get Bell's palsy more than once. So if you get what seems like a second episode, see your doctor because your symptoms may be caused by an underlying condition.

Where to get more help

The symptoms of Bell’s palsy might make you feel anxious or self-conscious. You might want to talk to other people who have the condition. There are various charities and support groups. For example, in the UK, the Bell's Palsy Association (bellspalsy.org.uk) is a charity that may be able to help.

References