Bell's palsy
Bell's palsy is a sudden, temporary weakness or paralysis of the facial muscles, typically affecting only one side of the face. It occurs when the nerve that controls facial muscles becomes inflamed, swollen, or compressed.
Overview
Bell's palsy is a sudden, temporary weakness or paralysis of the facial muscles, typically affecting only one side of the face. It occurs when the nerve that controls facial muscles becomes inflamed, swollen, or compressed.
Understand this condition
The facial nerve travels through a narrow corridor of bone on its way to the muscles. When this nerve swells, it gets pinched against the bone, blocking the signals that tell your face to move.
Why it happens
Inflammation is usually triggered by a dormant virus that reactivates and attacks the nerve sheath. As the nerve swells inside its tight bony canal, blood flow is restricted, causing temporary nerve dysfunction.
Real-world scenarios
- •This often appears as a sudden inability to smile on one side.
- •People may notice food falling out of their mouth while eating.
- •This often appears as an eye that will not close or blink.
- •People may notice a sharp pain behind the ear before drooping starts.
Common vs serious explanations
- •Recent viral infection lingering in the nervous system
- •Mild inflammation of the facial nerve pathway
- •Temporary nerve compression from local swelling
- Ischemic stroke or transient ischemic attack (TIA)
- Brain tumor pressing on the facial nerve path
- Lyme disease causing neurological complications
- Ramsay Hunt syndrome involving the shingles virus
Symptoms
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Causes
- •Viral infection (e.g., herpes simplex)
- •Inflammation of the facial nerve
- •Swelling within the narrow bone canal of the face
Risk factors
- •Pregnancy (especially third trimester)
- •Diabetes
- •Upper respiratory infections (flu or cold)
- •Family history of the condition
How it progresses
4 stages- Stage 1 — SilentOften no noticeable symptoms; only detected on routine exam.Often missed
- Stage 2 — Early changesSubtle peripheral or functional changes begin to appear.
- Stage 3 — EstablishedClear symptoms that interfere with daily activities.
- Stage 4 — AdvancedSignificant impairment if untreated; requires specialist care.
How it's diagnosed
- •Physical examination of facial movements
- •Electromyography (EMG)
- •MRI or CT scans to rule out other causes
Treatment options
General educational information only — no dosage advice. Always follow guidance from a qualified clinician.
- •Corticosteroids to reduce inflammation
- •Antiviral medications
- •Physical therapy to stimulate facial muscles
- •Protective eyewear and eye drops
- •Using an eye patch at night
- •Applying lubricating eye drops/ointments
- •Applying warm, moist compresses to the jaw
- •Practicing facial muscle exercises
Complications
- •Reduced quality of life
- •Worsening symptoms over time
- •Recurrence of bell's palsy
Prevention
- •Maintain a healthy lifestyle
- •See a clinician for routine check-ups
When to seek help
- •Symptoms persist beyond a few days
- •Symptoms interfere with daily activities
- •New or worsening symptoms appear
- •Concerning changes related to bell's palsy
- Sudden weakness on one side of the body
- Slurred speech
- Vision changes
- Severe headache
- Confusion or dizziness
In any emergency, call your local emergency number or go to the nearest emergency department.
Real-world questions
- ›Can Bell's palsy cause headaches?
- ›Is Bell's palsy reversible?
- ›How quickly does Bell's palsy progress?
- ›Is Bell's palsy hereditary?
- ›Can Bell's palsy be prevented?
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Frequently asked questions
Possible causes of Bell's palsy include Viral infection (e.g., herpes simplex), Inflammation of the facial nerve, Swelling within the narrow bone canal of the face.
Bell's palsy is generally moderate, but severity can vary. Seek care if symptoms are severe or persistent.
Duration varies between individuals. Many cases improve with appropriate care, while others may persist longer and require ongoing management.
Some milder cases may improve with rest and self-care. If symptoms persist or worsen, consult a healthcare professional.
Consider seeing a clinician if symptoms are severe, persistent, worsening, or if you have any concerns related to general.
Sources
Information based on general medical references such as:
Last reviewed: May 2026