Bell’s Palsy: Overview, Causes, and Symptoms

Bell’s palsy is a form of facial paralysis that affects approximately 0.02% of the population. The likelihood of developing this condition increases with age and is higher in individuals with certain medical conditions. Those with cold sores, flu-like illnesses, diabetes, tumors, skull or facial injuries, or Lyme disease are more prone to developing Bell’s palsy.

Causes and Risk Factors

The exact cause of Bell’s palsy remains unclear, but it is often linked to viral infections. The herpes simplex virus, responsible for cold sores, is considered one of the primary triggers. Other contributing factors include:

• Flu-like illnesses such as the common cold or upper respiratory infections

• Chronic conditions like diabetes, which may increase nerve vulnerability

• Head trauma or injuries affecting the facial nerve

• Lyme disease, caused by tick bites in certain geographic areas

Sudden Onset and Symptoms

One of the most unsettling aspects of Bell’s palsy is its sudden onset. Symptoms often appear without warning. You might go to bed with a symmetrical face and wake up the next morning to find one side of your face paralyzed or weakened.

In some cases, mild symptoms such as numbness or muscle weakness on one side of the face might develop a day or two before full paralysis sets in. Other early warning signs include:

• Pain behind the ear on the affected side

• Hyperacusis (when normal sounds feel uncomfortably loud)

• Twitching or slight muscle contractions before complete weakness occurs

Progression of Symptoms

The symptoms of Bell’s palsy usually peak within 24 to 48 hours of their first appearance. Common signs include:

• Sudden weakness or paralysis on one side of the face

• Drooping of the mouth or eyelid

• Difficulty closing the eye on the affected side

• Trouble chewing, sipping, swallowing, or speaking clearly

Many patients initially fear they are having a stroke due to the facial muscle weakness. However, there is a key difference: Strokes typically affect other areas of the body as well, such as the arms or legs, whereas Bell’s palsy is limited to the facial muscles.

When to Seek Medical Help

If you notice any of the following symptoms, seek medical attention immediately:

• Sudden onset of facial weakness or paralysis

• Pain behind the ear or an unexplained increase in sensitivity to sound

• Difficulty closing your eye on one side

Early diagnosis and treatment can significantly improve the chances of a full recovery. Although the condition often resolves on its own, timely medical intervention—such as corticosteroids, physical therapy, or acupuncture—can accelerate healing and prevent complications like permanent muscle weakness or contractures.

In conclusion, Bell’s palsy is sudden and often frightening, but understanding its symptoms and causes can help ensure timely treatment and a better outcome.