Bell’s palsy: Symptoms, Causes and Treatment


It is a disease, which is also known as facial paralysis. Bell’s paralysis, more accurately, severe paralysis or weakness of the facial muscles on one side of the face.

Although there is no unanimous opinion, it is believed to be due to a swelling of the nerve that controls the muscles of the face.

However, although it is a delicate disease, most individuals achieve a complete recovery from Bell’s palsy.

Patients, when they have the disease, often find that suddenly they can not control their facial muscles, usually on one side of the face. Making one side of the face tilt; It can also affect saliva and the production of tears, and the sense of taste.

A person may have Bell’s palsy early in the morning – they wake up and find that one side of the face does not move.

Most people who suddenly experience the symptoms think they are having a stroke. However, if the weakness or paralysis only affects the face it is more likely to be Bell’s palsy.

Approximately 1 in every 5,000 people develop Bell’s palsy each year. It is classified as a relatively rare condition. In very rare cases, Bell’s palsy can affect both sides of an individual’s face.


The facial nerves control the blinking, the opening and the closing of the eyes, but also the smile, the salivation, the lachrymation (production of tears) and the frown. They also connect with the stapes muscles – a bone in the ear involved in hearing.

When the facial nerve is malfunctioning, as in Bell’s palsy, the following symptoms may occur:

  • Sudden paralysis / weakness on one side of the face.
  • It can be difficult or impossible to close one of the eyelids.
  • Irritation in the eye because it does not blink and becomes too dry.
  • Changes in the amount of tears that the eye produces.
  • Parts of the face may fall, like one side of the mouth.
  • Drool from the side of the mouth. The amount of saliva produced changes.
  • Difficulty with facial expressions.
  • The sense of taste can be altered.
  • An affected ear can lead to sound sensitivity (hyperacusis). The sounds seem louder.
  • Pain in the front or behind the ear on the affected side.
  • Headache.

Causes of Bell’s palsy

The facial nerve controls most of the muscles of the face and parts of the ear. The facial nerve passes through a narrow opening of bone from the brain to the face.

If the facial nerve is inflamed, it will press against the cheekbone or pinch in the narrow gap; This can result in damage to the protective covering of the nerve.

If the protective covering of the nerve is damaged, the signals that are sent from the brain to the muscles of the face are not transmitted correctly, which leads to facial muscles to weaken or paralyze, as with Bell’s Paralysis.

However, scientists are not completely sure of the exact causes.

Experts believe that it is most likely caused by a virus, usually the herpes virus, which inflames the nerve. The herpes virus is the one that also causes cold sores and genital herpes.

Other viruses have also been linked to Bell’s palsy:

  • Varicella and herpes zoster virus
  • The virus that causes mononucleosis (Epstein-Barr)
  • Cytomegalovirus
  • Mumps virus
  • Influenza B
  • Hand-foot-and-mouth disease (coxsackievirus)

The risk factors of Bell’s palsy

The exact reasons why Bell’s palsy occurs are not understood; however, associations have been found between migraine and facial and limb weakness.

In this sense, a study conducted in 2015 found that people with migraine may have an increased risk of Bell’s palsy.

The condition most commonly affects:

  • Persons from 15 to 60 years old
  • People with diabetes or upper respiratory diseases
  • Pregnant women – especially during the third trimester
  • Women who gave birth less than 1 week ago
  • Bell’s palsy affects men and women equally.


The AMA (American Medical Association) says that treatment is most effective when administered early; so patients should see their doctor as soon as they experience symptoms.

Diagnosis of Bell’s palsy by a process of elimination (diagnosis of exclusion)

The doctor will look for evidence of other conditions that may be causing facial paralysis, such as a tumor, Lyme disease or stroke. This will involve checking the head, neck and ears of patients. They will also carefully check the facial muscles and determine if other nerves apart from the facial nerve are affected.

If all other causes can be excluded, the doctor will diagnose Bell’s palsy. If the doctor is still not sure, the patient can be referred to an otolaryngologist. The specialist will examine the patient and may also request the following tests:

  • Electromyography (EMG) – electrodes are placed on the patient’s face. A machine measures the electrical activity of the nerves and the electrical activity of the muscles in response to stimulation. This test can determine the extent of nerve damage, as well as its location.
  • Magnetic Resonance Imaging: Computed tomography or x-rays are good at determining if other underlying conditions are causing the symptoms, such as a bacterial infection, skull fracture, or a tumor.

Therefore, it is always advisable to maintain communication with the doctor and avoid self-medication as much as possible, under the pretext of triggering major problems that could be avoided.

What are the treatments for Bell’s palsy?

There is no treatment that can stop it. If your doctor suggests that your symptoms could be triggered by the herpes virus (herpes simplex 1) or shingles, you may be given an antiviral medication, such as acyclovir. But there is no research to show that these medications work to reduce the symptoms of Bell’s palsy.

Your doctor may also give you a short course of corticosteroids (such as prednisone). The goal is to decrease the swelling of your facial nerve. This can shorten the duration of Bell’s Paralysis symptoms.

Meanwhile, your doctor will instruct you to take special care to protect your eye from the affected side. He may suggest that you wear an eye patch, since you will not be able to blink. If your eyes are drying less than normal, you may need to use eye drops to prevent them from drying out.

Finally, the doctor can suggest a massage of the facial muscles. In very rare cases, where the symptoms do not improve after a while, it may suggest surgery to reduce the pressure on the facial nerve.