Frown lines are the vertical or diagonal lines that form between the eyebrows — often called glabellar lines or the “11s” because of the parallel pattern they create. They develop from repeated contraction of the muscles that draw the brows together and downward, and become more prominent as skin loses collagen and elasticity over time. This guide covers everything you need to know: what causes frown lines, how they differ from forehead wrinkles, what treatments are available, what results look like, and what treatment costs in Australia.
Quick answer: Frown lines are caused by repeated contraction of the corrugator supercilii and procerus muscles between the eyebrows, combined with progressive collagen loss and UV-related skin ageing. They begin as dynamic lines that appear with expression, and with time become static lines visible at rest. Non-surgical muscle relaxant treatments are the most established and effective option, with results typically lasting three to four months.
What causes frown lines?
Frown lines are created by two primary muscle groups that work together to draw the eyebrows inward and downward: the corrugator supercilii muscles, which pull the inner brow diagonally downward, and the procerus muscle, which draws the skin between the brows downward. Every time you concentrate, squint, frown, or make any expression that brings the brows together, these muscles contract and create a temporary crease in the overlying skin.
In young skin with good collagen and elasticity, that crease disappears completely when the face relaxes. Over time, collagen synthesis progressively declines — a process confirmed in a 2025 systematic review in Cosmetics — and the skin gradually loses its ability to fully smooth after each contraction. The result is lines that start appearing at rest, not just during expression.
UV radiation accelerates this process significantly. Cancer Council Australia notes that Australia experiences some of the highest UV radiation levels in the world, making photoageing a more significant contributor to early line formation here than in many other countries. An ABS survey covering the 2023–24 summer found that only 38.1% of Australians used sunscreen on most days — meaning cumulative UV damage continues to compound throughout most people’s lives.
Frown lines can also be influenced by stress, habitual squinting (including during screen use), strong muscle activity, and genetics. Some people simply have more powerful corrugator muscles than others and develop pronounced glabellar lines earlier.
Dynamic vs static frown lines
Like forehead wrinkles, frown lines progress through two distinct stages — and understanding where someone sits on that spectrum determines what treatment will work best.
Dynamic frown lines only appear when the corrugator and procerus muscles contract. When the face is at rest, the skin between the brows is smooth. Dynamic lines respond very well to muscle relaxant treatments, which temporarily reduce the strength of these contractions and allow the overlying skin to smooth.
Static frown lines remain visible even when the face is fully relaxed. They represent the accumulated effect of years of muscle use on skin that has progressively lost its structural support. Static glabellar lines typically require a combination approach — muscle relaxant treatment to stop further deepening, often combined with treatments that address skin quality or volume in the area between the brows.
| Feature | Dynamic frown lines | Static frown lines |
|---|---|---|
| Visible at rest? | No — only with expression | Yes — even when relaxed |
| Primary cause | Corrugator/procerus muscle contraction | Collagen loss + cumulative muscle use |
| Typical onset | Mid-20s onwards | Mid-30s onwards |
| Best treatment | Muscle relaxant treatment | Combination approach |
| Preventable? | Yes, with early intervention | Partially, with early intervention |
How frown lines differ from forehead wrinkles
Frown lines and forehead wrinkles are both upper face concerns, but they are caused by different muscles and require different clinical considerations. Understanding the distinction matters for treatment planning — and for understanding why treating one area without considering the other can sometimes produce suboptimal results.
Forehead wrinkles are horizontal lines created by the frontalis muscle, which runs across the full width of the forehead and is responsible for lifting the brows. Frown lines are vertical or diagonal lines created by the corrugator supercilii and procerus muscles, which pull the brows inward and downward — the opposite direction to the frontalis.
Research published in the Yonsei Medical Journal (2023) found that in 83.3% of study participants, contraction of the frontalis muscle also displaced the glabellar skin — the area where frown lines form. This confirms a functional relationship between the two muscle groups: they are anatomical antagonists, meaning one set lifts while the other depresses. This is why treating the forehead without considering the glabella — or vice versa — can shift the balance between these muscle groups and produce results that look unnatural or feel off.
In our clinical experience, most people presenting with frown lines also have some degree of forehead wrinkle activity, and we assess both areas together in every consultation. For the full picture on how these two concerns compare, read our guide to forehead wrinkles vs frown lines.
Treatment options for frown lines
The glabellar area — the region between the eyebrows where frown lines form — is one of the most well-studied treatment sites in non-surgical cosmetic medicine. There is a strong evidence base for muscle relaxant treatments in this area, and it is typically one of the most responsive areas of the face to treatment.
Muscle relaxant treatments
Muscle relaxant treatments work by temporarily reducing the activity of the corrugator supercilii and procerus muscles, preventing them from creating the repeated creasing that forms and deepens frown lines. The glabellar complex is considered a higher-priority area than the forehead in most treatment plans because the muscles involved are typically stronger, the lines tend to be more pronounced, and the emotional expression associated with this area — a furrowed brow can read as angry, stressed, or tired — has a significant impact on how people are perceived and how they perceive themselves.
A 2022 systematic review and meta-analysis published in the Aesthetic Surgery Journal reviewed 4,268 upper face treatment sessions and found that the overall complication rate for muscle relaxant treatments in the glabellar and forehead regions was 16%, with the vast majority of events being mild and transient — most commonly temporary headache or localised skin responses. No severe treatment-related complications were identified across the included studies.
Results from muscle relaxant treatments for frown lines typically become visible within three to seven days, with full effect at two weeks. Duration is typically three to four months. The glabellar complex often responds consistently across repeat treatments, and many patients find their results become more predictable over time with regular maintenance.
One clinical consideration specific to frown lines: the corrugator and procerus muscles are powerful and are used very frequently throughout the day — in concentration, reading, screen use, and emotion. This means the muscles tend to regain activity at a similar rate to the forehead, though individual variation is significant.
Combination approaches for static frown lines
For people with established static frown lines — lines that remain visible when the face is fully relaxed — muscle relaxant treatments alone may not achieve complete resolution. In these cases, a combination approach that includes treatment to address the structural depth of the line may be considered alongside muscle relaxant treatment. Our approach is always to assess what is realistic in your specific situation before making any recommendations.
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What results look like
For dynamic frown lines treated with muscle relaxant treatments, most people see a significant reduction in the depth of the “11s” when they frown, and a noticeable softening of lines at rest where those had begun to form. The area between the brows becomes smoother, and many people report that they no longer look as though they are frowning or stressed when their face is neutral.
The completeness of results depends on how established the lines are. People who begin treatment when frown lines are still primarily dynamic achieve more complete smoothing than those who start when deep static lines are already present. Deep static lines that have been present for many years may still show improvement with treatment, but a residual crease at rest is a realistic expectation in these cases.
In our clinical experience, frown lines are one of the areas where people most frequently report a meaningful quality-of-life improvement after treatment — not because of how the lines looked to others, but because of how the person felt about their own face in photos, on video calls, and in the mirror. That persistent furrowed appearance, even when relaxed, is something many people find disproportionately distressing.
Results typically last three to four months before the muscles gradually regain their activity and lines begin to return. With regular maintenance, the lines often soften progressively over time as the muscle adapts.
Before and after treatment for frown lines.
Before and after treatment for frown lines.
Before and after treatment for frown lines.
Before and after treatment for frown lines.
How much does frown line treatment cost in Australia?
Frown line treatment in Australia typically costs between $500 and $2,000 per appointment. Where you land in that range depends on the seniority and experience of the treating clinician, the clinic, the specific treatment modality, and whether the frown lines are being treated in isolation or as part of a combined upper face plan.
Treating frown lines alone tends to sit at the lower end of the range. Combined upper face treatments — addressing frown lines, forehead wrinkles, and lateral eye area together — typically sit higher. Combination treatments that include skin quality work alongside muscle relaxant treatment will generally cost more than a single-modality appointment.
It is worth asking clinics whether they charge per area, per unit, or as a flat fee. At Cosmetic Connection, we use a flat-fee model, which means full pricing transparency before you arrive. Our pricing is available on the flat-fee services page.
Cosmetic treatments are not covered by Medicare or private health insurance. Some clinics offer payment plan options.
Suitability — who is a good candidate
Muscle relaxant treatments for frown lines are suitable for most healthy adults. The ideal candidate has dynamic frown lines — lines that appear primarily with expression — and wants to prevent those lines from becoming permanent over time.
People who are pregnant or breastfeeding are not suitable candidates. Those with certain neuromuscular conditions or medications that interact with the treatment may not be suitable either. As with all cosmetic treatments, a proper suitability assessment before proceeding is essential. This is a central part of our approach at Cosmetic Connection — we will always tell you honestly if treatment is not appropriate for your situation.
For people who are not yet sure whether treatment is right for them, our patient journey starts with understanding your concerns and goals before making any recommendations. You can read more about how that process works.
Prevention
The most effective preventative measures for frown lines are consistent sun protection with broad-spectrum SPF, which limits the UV-driven collagen breakdown that accelerates line formation; being mindful of habitual squinting or frowning during screen use; and starting muscle relaxant treatments before lines become static.
Beginning treatment when frown lines are still dynamic — visible only with expression — is one of the most effective preventative strategies available. Keeping the corrugator and procerus muscles moderately relaxed between treatments allows the overlying skin to recover structural support rather than continuing to crease.
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Frequently asked questions
What are frown lines also called?
Frown lines are also referred to as glabellar lines, glabellar folds, or the “11s” — a reference to the parallel vertical lines that often form between the eyebrows. The technical anatomical term for the region is the glabella.
Can frown lines make me look angry even when I’m not?
Yes — this is one of the most common concerns we hear. Deep frown lines at rest can create an expression that reads as angry, stressed, or unapproachable, regardless of how someone actually feels. This is particularly common in people with strong corrugator muscles who develop pronounced lines relatively early. Treatment can soften this resting expression significantly.
How long do results last?
Results from muscle relaxant treatments for frown lines typically last three to four months. The glabellar muscles are used frequently throughout the day and tend to regain activity at a similar rate to the forehead. Regular maintenance every three to four months is typically recommended.
Are frown lines the same as forehead wrinkles?
No — they are distinct concerns caused by different muscles. Frown lines are vertical or diagonal lines between the eyebrows, caused by the corrugator and procerus muscles. Forehead wrinkles are horizontal lines across the forehead, caused by the frontalis muscle. The two areas are anatomically connected and are often assessed and treated together, but they are separate concerns.
Do frown line treatments hurt?
Most people describe the sensation as a mild pinch. The glabellar area is generally well tolerated. Discomfort is brief and resolves immediately after treatment. Numbing cream is not usually required, though it is available on request.
Is there downtime after frown line treatment?
There is minimal downtime. Most people return to normal activities immediately. Minor redness or a small mark at the treatment site can occur but typically resolves within a few hours. We recommend avoiding vigorous exercise, heat exposure, and lying flat for several hours after treatment.
References
- Bar O, Valiukevičienė S. (2025). Skin Aging and Type I Collagen: A Systematic Review of Interventions with Potential Collagen-Related Effects. Cosmetics, 12(4), 129. https://www.mdpi.com/2079-9284/12/4/129
- Cancer Council Australia. UV Radiation Prevention Policy. https://www.cancer.org.au/about-us/policy-and-advocacy/prevention/uv-radiation
- Australian Bureau of Statistics. (2024). Sun protection behaviours, Nov 2023 to Feb 2024. https://www.abs.gov.au/statistics/health/health-conditions-and-risks/sun-protection-behaviours/latest-release
- Kwon IJ, Lee W, Moon H-J, Lee SE. (2023). Dynamic Evaluation of Skin Displacement by the Frontalis Muscle Contraction Using Three-Dimensional Skin Displacement Vector Analysis. Yonsei Medical Journal, 64(7), 440–447. https://pmc.ncbi.nlm.nih.gov/articles/PMC10307676/
- Zargaran D, Zoller F, Zargaran A, et al. (2022). Complications of Cosmetic Botulinum Toxin A Injections to the Upper Face: A Systematic Review and Meta-Analysis. Aesthetic Surgery Journal, 42(5), NP327–NP336. https://academic.oup.com/asj/article/42/5/NP327/6530404
