Bell's palsy usually appears suddenly, often overnight. The primary symptom is weakness and paralysis on one side of the face. You may find that you can't make the same expressions as usual. Typically, you'll be unable to fully close one eye. Other possible symptoms include:
- altered sense of taste
- facial pain, pain in or behind the ear (in fewer than 50% of cases)
- no tears in one eye
- sensitivity to noise on the affected side
There's none of the confusion, language difficulty, or crushing headache that's commonly seen in stroke victims. You may have some trouble talking, but it's purely muscular, whereas stroke victims have difficulty finding the words they need.
Usually, the symptoms appear at once. Occasionally, they worsen over a few days. Steady, progressive paralysis over several weeks is not a sign of Bell's palsy.
The most serious complication seen in Bell's palsy is permanent mild facial paralysis. This is found in a minority of cases. Overall, about 80% recover completely over weeks to months, and most of the rest improve.
Another complication is increased risk of stroke. Stroke prevention and follow-up is recommended.
Some people don't recover completely. This is more likely in people who are older than 60 or who are experiencing weakness or paralysis on both sides of the face.
People who don't recover completely may be left with one or more of the following symptoms:
- abnormal blink
- asymmetrical smile
- buccinator paralysis (food caught in cheek of paralyzed side)
- corneal damage
- drooling of liquids from corner of paralyzed mouth
- dry eye
- excessive perspiration
- frozen muscle in the nostril area
- hyperacusis (perceiving sounds as unusually loud)
- impaired taste
- impaired speech
- synkinesis (involuntary movement associated with a voluntary movement)