Quanliao

What is SI18?

SI18 (Quanliao) is a Small Intestine channel point in the hollow just under the cheekbone, directly below the outer corner of the eye.

Its Chinese name means "cheekbone crevice", which is a fair description of where your fingertip lands. It is listed in the classical texts and taught in every modern acupuncture curriculum, usually as a local point for the cheek, jaw and face rather than for anything happening elsewhere in the body.

In traditional theory, SI18 is where the Small Intestine channel runs across the face on its way to the ear. Practitioners have used it for centuries for facial pain, toothache, cheek swelling, eyelid twitching and one-sided facial weakness. More recently it has been borrowed by cosmetic acupuncture and facial massage routines.

Two things need saying once, and this is the place for them. A point's long history tells you that people used it, not that it works, and not that it is safe for you. Tradition and evidence are separate axes, and on this page they are graded separately.

The honest verdict on the evidence: weak. SI18 shows up inside needling protocols for Bell's palsy and facial nerve pain, but it is almost never tested on its own, and research on finger pressure at this point is essentially absent. What you can reasonably expect from pressing it is a few minutes of local warmth and some relief of muscle tightness around the cheek and jaw. That is a real but modest thing, and it is not a treatment for a nerve problem.

Everything described here is self-applied finger pressure on the surface of your own face. The face is thin-skinned, sits close to the eye, and carries a lot of small nerves and vessels, so the sensible pressure here is much lighter than anything you would use on a shoulder or a calf.

Where is SI18 and how do you find it?

SI18 sits in the small dip on the lower edge of the cheekbone, on a vertical line dropped straight down from the outer corner of the eye.

• Start at the outer eye corner. Find the point where your upper and lower eyelids meet at the outside of the eye. This is your vertical reference line, not the spot itself.
• Drop straight down. Move your fingertip down from that corner, keeping it on the same vertical line, until you meet the solid ridge of the cheekbone.
• Feel for the lower border. Trace down the front of that bony prominence until the bone ends and the tissue softens. The gap is usually about 2 to 3 cm (roughly one to one and a half thumb-widths) below the lower eyelid.
• Settle into the hollow. SI18 is in the shallow depression right at that lower border, just under the bone rather than on top of it.
• Check the feel. Pressing gently often gives a dull, slightly tender ache that may spread toward the upper teeth, the nose or the ear. Sharpness or a jolt means you have moved onto something else.
• Test it with your jaw. Clench lightly and you should feel the masseter chewing muscle bulge below your finger. SI18 stays above that bulge.

There is one on each side of the face, and they are mirror images. Sources agree closely on this landmark, so if your finger is in the hollow under the cheekbone below the outer eye corner, you are on it.

Two neighbours cause confusion. ST3 sits further in, below the pupil rather than the outer eye corner. ST7 sits further back, in front of the ear in the notch below the cheekbone arch. SI18 is between them, at the outer-corner line.

How do you apply pressure to SI18?

1. Wash your hands first. You are working on facial skin close to the eye, so clean hands and short nails matter more here than almost anywhere else on the body.
2. Sit and steady yourself. Rest your elbows on a table or a desk. A supported arm gives far steadier pressure than one held in mid-air.
3. Use a flat fingertip. Place the pad of your middle or index finger in the hollow under the cheekbone. Use the pad, never the nail or a fingertip pressed in edge-on.
4. Press lightly and straight in. Aim for gentle pressure that you would rate about 2 or 3 out of 10. Facial tissue is thin and the bone is right there, so hard pressure just bruises skin.
5. Hold or circle. Either hold still for 30 to 60 seconds, or make slow small circles for the same time without dragging the skin.
6. Do both sides. Work one side then the other, or both together with matching fingers, for a total of two to three minutes.
7. Repeat sparingly. Once or twice a day is plenty. Daily use over weeks is reasonable if it stays comfortable.
8. Finish gently. Ease off slowly rather than lifting away sharply, and let the area settle before touching it again.

Stop straight away if pressing causes sharp pain, a shooting or electric sensation, numbness, pins and needles, watering eyes, blurred vision or dizziness. Those are signals to stop, not signals that it is working.

Do not press on the eyeball or the bony rim of the eye socket. If you have moved upward onto the orbital rim, you have gone too high and should reposition at the lower edge of the cheekbone.

Never break the skin, and never use a tool, a needle or anything sharp. Finger pressure only.

What is SI18 traditionally used for?

• One-sided facial weakness. Tradition used SI18 for a drooping or paralysed face, and it appears in modern needling protocols for Bell's palsy. The trials are small, poorly blinded and test whole point combinations, so no effect can be credited to SI18 by itself. Sudden facial droop is a medical emergency until proven otherwise.
• Facial nerve pain. Classical sources list it for stabbing pain across the cheek, which maps onto what we now call trigeminal neuralgia. Reviews of acupuncture for this condition exist but rate the evidence as low quality. Acupressure specifically has not been tested here.
• Toothache in the upper jaw. SI18 sits over the upper back teeth, and the tradition used it for pain there. There is no useful human trial evidence for pressing it for dental pain, and toothache almost always has a cause a dentist needs to find.
• Cheek and jaw tension. Gentle pressure over tight chewing muscles can feel loosening in the short term, which is plausible as simple local massage rather than anything channel-specific. Expect minutes to hours of relief at most.
• Eyelid and cheek twitching. A long-standing traditional use. Most twitching settles on its own with sleep and less caffeine; there is no evidence SI18 changes its course.
• Sinus pressure under the cheek. Popular in modern self-care routines because the maxillary sinus sits behind this area. Any comfort is likely from gentle warmth and touch; it does not drain a sinus or treat an infection.
• Facial appearance routines. Cosmetic acupuncture and gua sha-style massage often include SI18. Claims about lifting, puffiness or wrinkles are marketing, not findings.

Taken together, the fair summary is that SI18 may offer brief, mild local comfort in the cheek and jaw. Nothing on this list is a substitute for diagnosis of facial pain, facial weakness or a sore tooth.

Are there tips for using SI18 effectively?

• Go lighter than you think. The skin over the cheekbone is thin and bruises easily. If you can see a red mark afterwards that lasts more than a few minutes, you pressed too hard.
• Use a mirror the first few times. Watching your fingertip helps you confirm you are below the cheekbone and well clear of the eye socket rim.
• Unclench before you start. Let the jaw hang slightly open with the teeth apart. A clenched jaw bunches the cheek muscles and makes the landmark harder to feel.
• Work both sides evenly. Even if only one cheek bothers you, treating both keeps the routine symmetrical and stops you leaning hard on the sore side.
• Pair it with warmth. A warm flannel on the cheek for a minute beforehand makes the area more comfortable to work on. Warm, not hot, and never over numb or inflamed skin.
• Keep the skin dry or lightly oiled. Dragging a dry fingertip across facial skin is irritating. Either press without sliding, or use a touch of a moisturiser you already tolerate.
• Set a short timer. One to two minutes per side is enough. People who press for ten minutes get sore skin, not better results.
• Keep a simple log. Note the symptom score before and after for a week or two. If nothing has shifted, the honest answer is that this point is not helping you.
• Fit it around sleep and caffeine. Jaw clenching and eyelid twitching respond far more to rest, stress and stimulant intake than to any point. Fix those first and judge the point second.
• Keep dental and medical appointments. Use SI18 alongside proper care for a tooth, sinus or nerve problem, never instead of it.

What do people get wrong with SI18?

• Expecting a cure. The commonest error. SI18 is not going to resolve facial paralysis, trigeminal neuralgia or an infected tooth, and any source promising that is overselling it.
• Pressing on the eye socket. Sliding upward onto the bony orbital rim or, worse, onto the eyeball. SI18 is at the lower edge of the cheekbone, several centimetres below the lower lid.
• Landing on bone. Grinding a fingertip into the hard prominence of the cheekbone instead of settling into the soft hollow just beneath it.
• Confusing it with ST3. ST3 sits below the pupil, closer to the nose. SI18 is further out, on the line below the outer corner of the eye.
• Confusing it with ST7. ST7 is in front of the ear, under the cheekbone arch. If your finger is near your ear, you have gone too far back.
• Using far too much force. Treating the face like a tight shoulder. Hard pressure here produces bruising and sore skin, nothing more.
• Using tools. Pressure wands, rollers with points, scraping tools or anything sharp. Fingertips only, and never anything that breaks skin.
• Pressing through a rash or spot. Working over acne, cold sores, shingles blisters or broken skin spreads infection and worsens the skin.
• Ignoring sudden facial droop. Reaching for a point instead of emergency care when one side of the face falls abruptly. That is a stroke sign until a doctor says otherwise.
• Missing a dental infection. Massaging a hot, swollen, throbbing cheek instead of calling a dentist. Spreading facial swelling needs urgent assessment.
• Overdoing the frequency. Pressing many times a day for weeks. More is not better, and the skin pays for it.

What does the research on SI18 actually say?

There is no good human research on pressing SI18 with a finger. What exists is needling research, where SI18 is one point among many in a protocol, so no finding can be attributed to this point on its own.

The largest body of work is on acupuncture for Bell's palsy, the sudden one-sided facial weakness that SI18 is traditionally associated with. Local facial points, SI18 among them, appear in many of these trials. A Cochrane systematic review of acupuncture for Bell's palsy concluded that the available trials were too small and too poorly reported to show whether acupuncture helps. Most people with Bell's palsy recover substantially on their own, which makes uncontrolled reports especially unreliable.

Facial nerve pain is the second area. Systematic reviews of acupuncture for trigeminal neuralgia generally report that the studies are small, mostly from a single region, often without credible sham comparison, and rated low or very low quality. Again, SI18 is typically embedded in a multi-point prescription.

A third strand is acupuncture during facial or dental procedures, where points around the cheek have been used for discomfort. This work is sparse and not specific to SI18.

For cosmetic claims — lifting, puffiness, skin quality — there is no controlled human evidence worth citing for this point.

What that means for you: nobody has shown that finger pressure on SI18 changes a facial nerve condition, a toothache or a sinus problem. Short-term easing of cheek and jaw muscle tightness is believable as ordinary local massage, and it is the only outcome you should realistically expect. Treat SI18 as comfort care and keep any real facial symptom under proper medical or dental review.