Usually, your body goes numb when your nerves get damaged, pinched, or irritated. A pair of nerves that run down the left and right side of your head let your face feel pain, temperature, touch, and other sensations.
Different sets of nerves control how your face moves. Any problems with these nerves can take away feeling from a part of your face. That can happen after dental surgery, an injury, or even sleeping in an odd position.
Medical conditions also can cause facial numbness.
Multiple Sclerosis (MS)
Numbness is one of the first and most common signs of MS. You may lose feeling in your face or other parts of your body. It happens because your body's immune system attacks the layer that protects nerve fibers. Without this layer, your nerves get damaged.
Shingles
This infection of the nerves is caused by the same virus that gives you chickenpox. Shingles can trigger a painful rash on one side of your face or body. Sometimes, it happens around one eye. About 1-5 days before the rash pops up, you may feel pain, burning, itching, tingling, or numbness on that part of your skin.
Stroke
This medical emergency happens when a blood vessel that pumps blood and oxygen to the brain gets blocked or bursts. One of the warning signs of a stroke is that your face suddenly goes numb or droops. Without blood and oxygen, brain cells die quickly, and the part of the body they control stops working.
With a stroke, every minute counts. The longer you wait to get treatment, the higher your chance of lasting brain damage. If you feel any numbness or weakness, suddenly feel confused or dizzy, and have trouble seeing, call 911.
Transient Ischemic Attack (TIA)
Also called mini or warning strokes, TIAs cause the same symptoms as a stroke, including numbness in your face. And like a stroke, it's caused by a clot in the brain. But unlike a stroke, the clot clears out quickly and symptoms only last a few minutes. Still, if one side of your face suddenly gets numb, if your speech slurs, or you have any other symptoms of stroke, call 911.
Bell’s Palsy
This condition makes the muscles on one side of your face weak or paralyzed. That side appears to droop, along with your eyelid and the corner of your mouth. Bell’s palsy happens when your facial nerve gets swollen, which affects how your face moves.
The symptoms, like drooling, may come on within hours or days. Most people with Bell’s palsy get better on their own within a few weeks.
Tumor
Some benign, or noncancerous, tumors can grow on or near the nerves that control sensation in your face and how it moves. If the tumor gets big enough, it can press on the nerve. Your symptoms depend on which nerve is affected. Your face may feel numb, or you could have trouble chewing. The muscles in your face may also get weak, or you may have hearing problems.
Brain Aneurysm
This is a weak, bulging spot in the wall of a brain artery. A small one may not cause symptoms. But as the aneurysm grows, it can press on brain tissues and nerves, and lead to numbness on one side of the face. You may also feel pain in one eye or have double vision.
If a brain aneurysm leaks or bursts, it can cause bleeding in the brain. Usually you'll have a very bad headache. You'll need emergency treatment.
Hemiplegic Migraine
This is a rare type of migraine that, along with a headache, can make one side of your body feel numb or weak. That can happen on your face, arm, or leg. Symptoms can last for a few hours to a few days.
