Bell's palsy, explained by someone who has been through it

Most people notice the first movement returning within two to three weeks, and around 70% recover completely within three to six months without lasting effects. Recovery that begins within the first three weeks is the single strongest predictor of a full result. A minority take up to a year, and some are left with residual weakness or synkinesis.

No, but you cannot safely tell them apart yourself, and please do not try. You may read that the forehead is the giveaway: that Bell's palsy weakens the whole side of the face including the forehead, while a stroke usually spares it. That pattern is real, and clinicians do use it, but it is a clue rather than a test. Strokes in the brainstem can weaken the forehead exactly as Bell's palsy does, which means a textbook 'Bell's palsy pattern' does not rule a stroke out. Sudden facial weakness is an emergency until a doctor says otherwise. Please call emergency services straight away, especially if you also have arm or leg weakness, slurred speech, confusion, vision changes, trouble walking, or a sudden severe headache. Being checked and told it is Bell's palsy costs you a few hours. Getting it wrong costs a great deal more, and Bell's palsy treatment is time-critical anyway.

Bell's palsy is inflammation and swelling of the seventh cranial nerve, where it passes through a narrow channel of bone. The swelling compresses the nerve and blocks its signals. The trigger is usually thought to be the reactivation of a dormant virus, most often herpes simplex, though it is formally classed as idiopathic, meaning no cause is confirmed in any individual case. It is not caused by cold weather or draughts, and it is not something you brought on yourself.

Gentle, well-timed facial retraining does support recovery, but the staging matters far more than the effort. During the flaccid phase, forcing strong movements achieves very little, because the nerve is not conducting signals yet. Later, as the nerve regrows, aggressive or asymmetric exercise can actually encourage synkinesis, the miswired movement where your eye closes as you smile. Small, slow, controlled movements in front of a mirror are what facial therapists recommend.