Frown lines and the "11s": causes and treatment
What causes them
A group of small muscles between the brows — the glabellar complex — pulls the brows together and down. It fires when you concentrate, when you are irritated, and reflexively when you squint into bright light or at a screen you cannot quite read.
The result is two vertical creases that look like the number 11. They are the lines most often described as making someone look angry or worried when they feel neither, which is why this is one of the most commonly treated areas on the face.
Treatment options
| Option | How it works | Results appear | Lasts | Where |
|---|---|---|---|---|
Wrinkle relaxers | Relaxes the glabellar complex so the brows stop being drawn together. | 2–10 days | 3–4 months | At Beauty Factory SD |
Dermal filler | Can soften a deep residual furrow once the muscle is relaxed. A secondary step, never the first. | Immediate | 6 months – 2 years | At Beauty Factory SD |
Microneedling | Improves the skin quality holding the crease, for lines etched at rest. | Weeks, over a course | Maintained with repeat sessions | At Beauty Factory SD |
Corrective vision or screen setup | Removes the squinting that drives the habit. Preventive, not corrective. | — | Ongoing | Elsewhere |
What we would recommend
A wrinkle relaxer, and this is the area where they perform best. The glabella is a well-defined muscle group with a well-established dosing pattern, and the change is usually the most noticeable of any single area on the face.
Typical ranges are 12 to 20 units of BOTOX®, Xeomin® or Jeuveau®, or 30 to 50 units of Dysport®. If your Dysport number looks alarmingly higher, it is not: one unit of BOTOX® equals about 2.5 units of Dysport®, the same way one inch equals 2.5 centimetres.
If a line remains visible at rest after the muscle has been relaxed for a treatment cycle or two, that residual crease can be addressed separately — but the correct order is muscle first, then anything else.
What it won't fix
Relaxing the glabella will not lift a heavy brow, and it will not change the shape of your eyes.
It will not remove a crease that is deeply etched at rest in one treatment. Skin that has been folded in the same place for twenty years needs a sustained period of not being folded before it flattens, which is why the second and third treatments often look better than the first.
And it does not stop you frowning as an expression — it reduces how hard the muscle pulls, not how you feel. A well-dosed result still lets you look concerned when you are.
What we use for frown lines (the "11s")
Common questions
What are the "11s"?
The two vertical lines that form between the eyebrows, named for their resemblance to the number 11. They are produced by the glabellar complex of muscles drawing the brows together.
How many units treat the glabella?
Typically 12 to 20 units of Botox, Xeomin or Jeuveau, or 30 to 50 units of Dysport. The exact number is determined by your injector after evaluating your facial muscles.
Why does Dysport need so many more units?
It does not need more product — the manufacturer counts units differently. One unit of Botox is equivalent to about 2.5 units of Dysport, in the same way one inch is 2.5 centimetres.
How long before frown lines come back?
Any neuromodulator typically lasts between 3 and 4 months, after which muscle movement gradually returns. Results are not permanent.
Stanislav Zayets, MD
Board-certified — American Board of Internal Medicine
Last reviewed August 7, 2026
Bring us the concern, not the treatment.
Tell us what's bothering you and we'll tell you which options genuinely address it — including when the answer is something we don't offer.