Does Bell's palsy cause weakness on one side?

Bell's palsy affects the facial nerve, which controls muscles used for smiling, blinking, and closing the lips. One side of the face may droop, the forehead may feel weak, or the eye may not close normally. Taste can change and pain near the ear may occur. Weakness in an arm or leg is not explained by the usual facial pattern of Bell's palsy and needs a different assessment.

Arrange prompt medical assessment for new one-sided facial weakness. Record the time it began and whether the forehead, eye, mouth, arm, or leg is affected. Follow advice about protecting an eye that cannot close, such as using recommended lubrication or covering, and avoid rubbing the eye. Do not start or stop treatment without clinical guidance.

Get emergency help if weakness starts suddenly with arm or leg weakness, trouble speaking or understanding, severe headache, difficulty walking, loss of vision, fainting, or confusion. These features may indicate a stroke. Emergency assessment is also needed if swallowing or breathing becomes difficult.

Ask whether the weakness fits a facial nerve problem, how to keep the affected eye protected, what treatment may be suitable, and which new symptoms should trigger emergency care.