Facial palsy doesn't arrive out of nowhere: before it comes, the body has already knocked three times

Many people think facial palsy means "you go to sleep, you wake up, and your face is suddenly crooked." It is not like that. It is more like someone who has walked for several days before finally reaching your face. Before arriving, it has knocked several times already; those knocks were all passed off as "didn't sleep well," "the ear hurts a little," or "probably too much internal heat."

Heed those knocks, and most cases of facial palsy can in fact be stopped before they ever break out.

First, know that "cramped" nerve

There are twelve pairs of cranial nerves; the one that governs facial expression is the facial nerve, the seventh. It is born cramped: after leaving the brain it must travel a long, narrow path, entering a small opening behind the ear called the stylomastoid foramen, then passing through the parotid gland, and finally dividing into five branches that spread across the forehead, the eye, the corner of the mouth, the chin and the neck.

The problem lies along that path. The passage is too narrow — so narrow that even a little swelling, even a little inflammation, can pinch the nerve.

The key is the pace: getting pinched is not a matter of one second, it is a gradual process. First the fine branches go wrong; only when the swelling slowly presses on the main trunk do the muscles of facial expression stop work altogether. And that stage — when the fine branches go wrong — is the warning sign.

Warning sign one: a dull ache behind the ear

This is the most classic signal, and the easiest to overlook. The stylomastoid foramen is behind the ear; it is where the facial nerve emerges. When the nerve first swells, this outlet is the first place to be compressed. So one or two days before facial palsy, many people feel a dull fullness or a dull ache behind the ear or around the base of the ear, and some can feel a little tenderness to the touch.

At this stage nothing shows on the face, and you assume it is just "wind in the ear." But if you pay attention, this is the first knock.

Warning sign two: a strange sense of taste, or an ear oversensitive to sound

The facial nerve does not only govern expression; it also carries taste, and controls a small muscle called the stapedius. So before facial palsy, some people find food tastes of nothing, or the front half of the tongue feels numb or wooden. Others find the ear unusually sensitive to sound: noises that never seemed loud suddenly become piercing.

Both signals are hidden, hidden enough that you yourself cannot say what is off. Yet precisely these arrive one step ahead of the crooked mouth.

Warning sign three: difficulty closing the eye, or tears that will not stop

A step further on, you feel that the eye is "a little disobedient": when you close it, a sliver of the eyeball shows — or the opposite, tears come for no reason and will not stop once they start. This is because the branches governing the eyelid and the lacrimal gland are being compressed too.

By this point the crooked mouth is very close. Yet many people still think nothing of it, putting it down to "eye strain."

How Chinese medicine sees it: wind moves first, yang fails first

Seen through the eyes of Chinese medicine, these three warning signs mean one thing: when upright qi becomes deficient, wind pathogen moves first.

Chinese medicine holds that "Wind is the leading cause of a hundred diseases." Wind pathogen is the most cunning of all; it loves the upper half of the body, the head and the face — because the head is the meeting of all yang (zhu yang zhi hui), where yang qi is at its fullest. Once your yang qi is depleted and the defensive qi is no longer secure, wind pathogen makes first for the face.

So you will see that before facial palsy strikes, most people have one of these foundations: late nights, overwork, exposure to cold, violent swings of emotion. Which of these does not first drain your yang qi and upright qi? Once upright qi loosens, that "wall against wind" springs a gap.

This is why, in preventing facial palsy, Chinese medicine does not stare at the face. It stares at whether you have worn yourself down into deficiency.

Six ways to prevent it

• Protect the area behind the ear and the back of the neck. These two places are the doors wind pathogen likes best. Cold weather, air conditioning, sitting by a car window: don't let cold wind blow straight on them. A thin scarf works better than anything.
• Don't stay up late. What facial palsy loves most is someone who has been up all night. Sleep is the quickest way to restore yang qi — the least trouble and the hardest to do.
• Don't let "tired" and "cold" stack up. Being a little tired on its own is fine; catching a little wind on its own is fine. What is most feared is being tired and chilled at once, when upright qi and wind pathogen arrive together — that is when things go wrong.
• Keep emotions on an even keel. Chinese medicine says that anger makes qi rise. Rage, sudden elation, deep grief: once the movement of qi is disordered, wind pathogen slips in through the gap.
• The moment a warning sign appears, stop. As soon as there is a dull ache behind the ear, a strange sense of taste or difficulty closing the eye — even if the face still looks straight — stop pushing through the late nights and the cold wind. Warm up, rest, and see a doctor. These knocks are the body's last chance for you.
• Nourish the spleen and stomach, and the qi and blood, in ordinary times. The spleen is the source of qi and blood; when the spleen and stomach are strong, upright qi is ample, and that wall can hold back the wind.

These groups should be especially careful

Pregnant and postpartum women, people with diabetes, long-term night owls, those who are constitutionally weak, and those who catch cold at the slightest thing. Their upright qi tends to be weaker, their risk of facial palsy is higher than average, and the six points above matter all the more to them.

Facial palsy is neither very serious nor entirely trivial. Mild cases ease within a few weeks; severe cases leave sequelae — a smile that squeezes the eye shut, tears that fall while eating — and regret comes too late.

But there is one mercy in it: it is not sudden. Before it comes, it reminds you again and again. The real danger is writing off every one of those knocks as "just wind." Heeding the body's reminders is worth more than anything.