Why does the Glabella make an "11" line?
The two vertical lines between the eyebrows are mostly formed by the repetitive contraction of the corrugator muscle. The corrugator pulls the eyebrow inward and downward towards the bridge of the nose. This movement is frequently repeated in low light, during a stressed gaze, or in front of a screen. When the skin repeatedly folds in the same direction, the collagen network weakens in this direction, and the line becomes static.
Two other muscles accompany this: the procerus (a small muscle that pulls the area between the eyebrows down) and the depressor supercilii (the muscle that pulls the inner end of the eyebrow down). When all three work together, the "frown" appearance emerges. The simultaneous targeting of these three is the definition of glabella botox.
Dose distribution and safe map
In female patients, the total dose is usually between 18-25 units (Botox/Xeomin equivalent). This dose is distributed as corrugator (approximately 6-8 units on each side), procerus (4-6 units), depressor supercilii (2-3 units if necessary). In men, the dose can increase by 30-50% because the muscle mass is larger. The distribution of the dose is more important than the total amount.
The depth of injection is also very important. The corrugator is deep; a superficial needle both misuses the dose and increases its spread. The procerus, however, can be more superficial. These details may seem theoretical in front of the camera, but in the clinic, they turn into a huge difference on the patient's face after 2 weeks.
Soft glabella
- 18-22 units total
- Slight muscle activity is preserved during mimicry
- Expression appears "rested," not "blank"
- Gradual reduction in 3 months
Stiff/frozen glabella
- 30+ units overdose
- No activity during mimicry
- Face gives the impression of a "mask"
- Recovery can extend to 5-6 months
Risk of eyebrow ptosis and precautions
The most feared complication of glabella botox is upper eyelid ptosis. This occurs if the needle is placed too low or if the dose spreads and reaches the levator palpebrae muscle. It is statistically rare (1-3%) but when it occurs, it can last 4-6 weeks and affect the patient's daily life. Therefore, corrugator injection is performed at least 1 cm above the eyebrow arch and deep.
Excessive elevation of the lateral ends of the eyebrows ("Spock brow" or "Mephisto brow") is another undesirable outcome. This results from suppressing the middle part of the corrugator too much and leaving the lateral ends free. The solution is an additional injection of 1-2 units into the lateral ends of the eyebrows two weeks later; this application is a standard fine-tuning at the control appointment.
Clinical note:If the patient has previously complained that "my eyebrows were tilted to one side" or if the upper eyelid is very thin/low, glabella botox is either performed at a low dose or planned in combination with filler. Routine applications provide high safety; exceptional anatomy requires high attention.
What to do if a static line remains?
After years of active corrugator use, a static line may have settled. This line softens after botox but may not completely disappear. In this case, I explain the second step to the patient: skin booster, microneedle radiofrequency, or very thin linear hyaluronic filler. This step is not done in the same session; the muscle is allowed to rest after botox, and after the skin relaxes, micro-intervention comes into play.
The improvement of a static line takes months, not weeks. If the patient came with the expectation of "it should be erased immediately," it is the physician's primary duty to align this expectation with reality. A hasty solution both yields poor results and disrupts the plan for subsequent years.
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Crow's Feet (Wrinkles): Thinness Around the Eyes