Botox for forehead lines: units, cost and results

Forehead wrinkles appear with frontalis muscle activity — the muscle that lifts the eyebrows — and Botox Cosmetic (onabotulinumtoxinA, made by Allergan, an AbbVie company) is approved to temporarily improve the appearance of moderate to severe forehead lines in adults.

The FDA added that indication on October 2, 2017.

It is one of four cosmetic areas on the label, alongside frown lines, crow's feet and platysma (neck) bands; no other cosmetic area is on it.

The drug works by blocking acetylcholine release at nerve endings — the label credits cleaving of a protein called SNAP-25 — which produces a partial, localized reduction in muscle activity.

Reinnervation, the slow regrowth of those nerve connections, is what makes the effect temporary.

The forehead carries a quirk: the label sets no forehead-only dose.

Forehead lines are treated together with the frown lines — 20 units to the forehead plus 20 units to the glabella, 40 units in total — a pairing the label says minimizes the potential for brow ptosis, a dropped or heavy brow.

The forehead is one entry in the series map of all Botox areas, and the Botox guide covers the drug as a whole.

The label's candidate is an adult with moderate to severe forehead lines associated with frontalis muscle activity.

Whether the treatment fits a particular person — medical history, medicines, how the brow moves — is a question for a licensed provider.

The label does draw some lines of its own.

Botox Cosmetic is contraindicated in people with known hypersensitivity to any botulinum toxin product or to any ingredient in the formulation, and it is not to be injected where there is an infection at the planned site.

People with neuromuscular disorders — myasthenia gravis, Lambert-Eaton syndrome and ALS are the label's examples — may be at increased risk of clinically significant effects, and the label advises caution in people with pre-existing cardiovascular disease or swallowing or breathing problems.

On pregnancy and breastfeeding there are no adequate human data and no data on whether the drug passes into breast milk.

Response is not uniform.

In exploratory analyses of the frown-line trials, 85% of 334 women were investigator-rated responders at day 30, against 59% of 71 men, and responses appeared lower in people 65 and older.

Cleveland Clinic adds a nuance about what toxin alone can do: it describes Botox as treating dynamic wrinkles, the lines that show when the muscle contracts, and says patients whose lines remain deep even at rest may benefit from adding a dermal filler.

The labeled dose is 40 units: 20 units across the forehead plus 20 units to the glabella, always treated together.

Because the label sets no forehead-only dose, a unit count quoted for the forehead alone is the injector's own plan rather than a labeled one.

Treating all three upper-face areas in one session raises the labeled total to 64 units — 20 forehead, 20 glabellar, 24 lateral canthal — while frown lines plus crow's feet without the forehead comes to 44 units.

Units are product-specific: the Botox Cosmetic label states its units cannot be compared to or converted into units of any other botulinum toxin product, so per-unit prices do not transfer between brands.

On money: Botox and other toxins are typically priced per unit or per treatment area, and the label doses act as a floor for the unit count an area needs, so an area's cost works out to roughly units times the per-unit price.

We could not confirm a current national average price for neuromodulator injections — the ASPS statistics report for 2025 that we checked omits fees for minimally invasive procedures — so the numbers that matter are the ones on a practice's quote: its price per unit, and the units it plans for the areas it treats.

Onset comes first.

The label's timing description is written from the frown-line studies, where muscle relaxation typically begins 1 to 2 days after injection and increases in intensity through the first week.

The American Academy of Dermatology's consumer guidance says most people see results within 3 to 7 days.

On duration, the label's one figure — approximately 3 to 4 months — is stated for glabellar (frown) lines, and the label gives no separate duration for forehead lines.

The two consumer references land in the same range: the American Academy of Dermatology gives 3 to 4 months for botulinum toxin improvements, sometimes longer, and Cleveland Clinic gives three to four months.

Because the label gives no forehead figure, a month count quoted for the forehead specifically is not a label figure.

What changes duration — dose, sex, the individual — is its own topic, covered in how long Botox lasts.

Spacing between sessions has its own label line: the safety and effectiveness of dosing more often than every 3 months have not been clinically evaluated.

The forehead has its own row in the trial data.

In the Botox Cosmetic forehead-line trials — 665 adults given 20 units to the forehead plus 20 units to the glabella — adverse reactions above placebo were headache in 9% (against 5% on placebo), eyelid ptosis in 2%, brow ptosis in 2% and skin tightness in 2%.

Brow ptosis — a heavy or dropped brow — is the reaction specific to this area, and the label manages it through placement and combination: the lower row of forehead injections sits at least 2 cm above the eyebrow, and the frown area is treated at the same time.

On top of the trial rates sit the effects any injection can cause — localized pain, swelling, redness, tenderness and bruising.

The label says adverse reactions generally occur within the first week and, while often transient, may last several months or longer.

Injecting botulinum toxin is the practice of medicine, as the American Med Spa Association (AmSpa) puts it — a prescription drug is being used to affect living tissue — so it belongs to a physician, an independent-practice nurse practitioner or another licensed professional working within their scope, under rules that vary by state.

The label adds its own requirement: those who administer Botox Cosmetic must understand the relevant neuromuscular and structural anatomy of the treated area.

The CDC advises consumers to get botulinum toxin injections only from a licensed, trained provider using product from an authorized source, and cautions that the procedure is not without risk even when FDA-approved product is given correctly.

Product authenticity is part of the check: FDA warned in April 2024 that counterfeit Botox had been found in multiple states and given to consumers for cosmetic purposes, with hospitalizations among the adverse events.

Genuine Botox Cosmetic shows U.S. License number 1889 on the vial and carton — the label says not to use it if that number is missing or the tamper-evident features look broken.

For credentials, questions to ask and red flags beyond any one treatment area, how to choose a med spa works through the decision end to end.