Forehead wrinkles—also known as horizontal forehead lines—are often the first visible sign of aging. These lines appear when the frontalis muscle contracts to lift the eyebrows, a natural movement during facial expressions like surprise or concern. Over time, repeated use of this muscle causes dynamic lines to become etched into the skin, even at rest.
Other contributing factors include:
Dehydration and lifestyle choices, like smoking
Genetics, which determine skin thickness and muscle strength
Sun exposure, which breaks down collagen and elastin
Stress, which increases facial tension
Frontalis muscle causes forehead lines
The frontalis muscle lifts the eyebrows and skin of the forehead, causing forehead lines to form
Anatomy of the frown lines
The muscles of facial expression responsible for creating frown lines (aka glabellar lines) are the corrugator supercilli and procerus muscles. The action of these muscles is to pull down the inner eyebrow and lower forehead, causing the skin of the glabella to crease. These muscles are often activated when an individual is stressed or unhappy, hence their negative association.
Forehead anatomy
The muscle of facial expression causing forehead lines is the frontalis muscle- a broad, sheet-like muscle that covers the entire forehead. The function of the frontalis muscle is to lift the eyebrows and skin of the forehead, inadvertently causing forehead lines to form in the process.
How Botulinum Toxin Treats Forehead Wrinkles
Botulinum Toxin is an injection of purified protein that temporarily relaxes targeted facial muscles. When injected into the frontalis muscle, it reduces the muscle’s ability to contract, softening the horizontal lines formed by repetitive motion.
At Bay Aesthetic Clinic, we take a conservative and artful approach. Rather than freezing your expression, our goal is to:
Prevent new lines from forming
Soften visible wrinkles
Preserve natural eyebrow movement
Treatment Process: What to Expect
1. Personalised Consultation
We will assess your facial muscle movement, wrinkle depth, brow height and symmetry. We’ll discuss your goals (e.g. subtle smoothing vs full wrinkle relaxation) and any prior Botulinum Toxin experience.
2. Targeted Injections
Botulinum Toxin is administered using ultra-fine needles at 5 to 7 strategic points across the forehead. The procedure takes around 5-10 minutes, with minimal discomfort.
3. No Downtime
You can resume most daily activities right after treatment. Minor swelling or pinpoint redness at injection sites typically subsides within an hour.
4. Visible Results in 3–5 Days
Forehead lines begin to soften around Day 3, with full results by Day 7 to 14. The outcome is a refreshed, rested look that still allows for natural expression.
Left untreated, dynamic forehead lines eventually become fixed lines, which are difficult to treat
How Many Units of Botulinum Toxin Are Needed for Forehead Wrinkles?
The number of Botulinum Toxin units required for forehead treatment can vary depending on individual muscle strength, forehead size, and desired level of movement.
Typical unit range:
Forehead (frontalis muscle): 12–24 units
Treating only the forehead without balancing the glabellar muscles may lead to unwanted side effects such as brow heaviness or a "spocked" look. That’s why most patients benefit from a combined approach—relaxing both the horizontal lines of the forehead and the vertical frown lines for natural, balanced movement.
Botulinum Toxin forehead lines injection points
Is Forehead Botulinum Toxin Right For Me?
You may be a good candidate if you:
Notice forehead lines that appear when eyebrows are raised and disappear at rest
Are in your 20s or 30s
Prefer non-surgical, quick treatments with natural results
Are looking for a more youthful, well-rested appearance
Risks and Side Effects of Forehead Botulinum Toxin
While forehead Botulinum Toxin is generally safe and well-tolerated when performed by a trained medical professional, there are some potential side effects to be aware of.
Common and temporary side effects:
Mild swelling, redness, or bruising at the injection site
Headache or a heavy feeling in the forehead (usually resolves in a few days)
Minor asymmetry if muscles respond unevenly (often correctable)
Less common risks:
Brow ptosis (drooping eyebrows): Can happen if Botulinum Toxin diffuses into the wrong muscle, especially if dosed too high or injected too low
Eyelid drooping (ptosis): Rare, usually linked to spread into the upper eyelid muscles
Over-freezing: An overly stiff look, especially if too many units are used without considering facial dynamics
Note: These risks apply to all Botulinum Toxin treatments. To minimise any complications, it’s important to have your treatment done by a doctor who can account for your individual facial profile and aesthetic goals.
Busting Botulinum Toxin Myths
“Will my forehead be frozen?” Not if done correctly. Our technique relaxes lines without eliminating natural movement. You’ll still be able to raise your eyebrows—just without the deep creasing.
“Is Botulinum Toxin only for older patients?” Not at all. Many patients in their 20s and 30s opt for forehead Botulinum Toxin as a preventive treatment to delay visible signs of aging.
“Is Botulinum Toxin addictive?” There’s no chemical addiction. Most patients return regularly simply because they enjoy the results and confidence it brings.
Why Choose Bay Aesthetics Clinic for Forehead Botulinum Toxin?
With over 10 years of experience in aesthetic treatments, Dr Hoe Ying Min serves as the Medical Director at Bay Aesthetics Clinic. She has extensive hands-on experience in lasers, injectables, body-shaping and skin-rejuvenation procedures, and is known for her careful, personalised approach that aims for natural-looking outcomes.
Bay Aesthetics Clinic and Medispa is a doctor-led clinic located in the Marina Bay Financial Centre that delivers medical aesthetics and medispa treatments in a calm, professional setting. With a focus on safety, visible results and accessibility, the team uses only US FDA and HSA-approved technology, applies a holistic view to beauty and wellness, and avoids hard-selling or pressure tactics.
Open from 11 am daily (until 8 pm Mon-Fri; 6 pm Sat/Sun) and conveniently situated within walking distance of two MRT stations
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B2-12 Marina Bay Link Mall, 8A Marina Boulevard, Marina Bay Financial Center, Singapore 018984
