What Is Facial Palsy?
Facial palsy refers to weakness or paralysis of the muscles on one or both sides of the face, caused by dysfunction of the facial nerve. This nerve controls facial expressions, blinking, and some aspects of taste and tear/saliva production. When it’s affected, it can cause drooping, uneven expressions, or complete loss of movement on the affected side.
Common Symptoms
- Drooping of one side of the face, mouth, or eyebrow
- Difficulty closing one eye completely
- Uneven smile or difficulty showing teeth on one side
- Drooling or difficulty controlling saliva
- Loss of taste on the front part of the tongue
- Increased sensitivity to sound in one ear
- Dry eye or excessive tearing on the affected side
- Difficulty with facial expressions like frowning or raising eyebrows
Bell’s Palsy: The Most Common Cause
Bell’s palsy is the most frequent cause of sudden facial palsy. It typically:
- Comes on suddenly, often over hours to a day or two
- Affects one side of the face
- Is thought to involve inflammation or swelling of the facial nerve, often following a viral infection
- Often improves on its own over weeks to months, especially with early treatment
Other Causes of Facial Palsy
- Stroke: Can cause facial weakness, but typically spares the forehead and often comes with other symptoms like arm weakness or speech difficulty
- Ramsay Hunt syndrome: Caused by reactivation of the shingles virus, often with a rash near the ear and ear pain
- Infections: Such as Lyme disease or middle ear infections
- Trauma: Injury to the face, skull, or facial nerve, including during certain surgeries
- Tumors: Growths affecting the facial nerve or surrounding structures
- Congenital conditions: Facial palsy present from birth
- Autoimmune or neurological conditions: Less commonly
Facial Palsy vs. Stroke: Why It Matters
Because facial drooping can be an early sign of stroke, it’s important to distinguish the two:
- Bell’s palsy usually affects the entire side of the face, including the forehead (difficulty raising the eyebrow on that side)
- Stroke-related facial weakness typically spares the forehead, since that part of the face receives nerve signals from both sides of the brain, and often comes with other symptoms like arm weakness, slurred speech, or confusion
Any sudden facial drooping should be evaluated urgently to rule out stroke.
How Is Facial Palsy Diagnosed?
- Detailed history and physical examination, checking whether the forehead is involved
- Assessment for signs of stroke or other neurological involvement
- Blood tests, if infection is suspected
- Imaging, such as MRI, in select or atypical cases
- Hearing tests, if Ramsay Hunt syndrome is suspected
Managing Facial Palsy
- Medications: Corticosteroids, especially when started early, and sometimes antiviral medications
- Eye care: Lubricating eye drops, ointment, and sometimes an eye patch at night to protect the eye if it doesn’t close fully
- Physical therapy: Facial exercises to support recovery and prevent muscle stiffness
- Treating the underlying cause: Such as antibiotics for Lyme disease or addressing an infection
- Surgical options: Considered in select, persistent cases
Recovery Outlook
Many people with Bell’s palsy see significant improvement within a few weeks to months, though recovery time varies. Early treatment tends to improve outcomes, and most people recover full or near-full facial function.
When to See a Doctor
Seek immediate medical attention for any sudden facial drooping or weakness, especially if it comes with arm weakness, slurred speech, vision changes, or confusion, as these could indicate a stroke. For facial weakness without these additional symptoms, prompt evaluation is still important to start appropriate treatment early.