Botox for crow's feet: units, cost and results

Crow's feet are the lines at the outside corners of the eyes, and they are on the Botox Cosmetic label as lateral canthal lines.

Botox Cosmetic (onabotulinumtoxinA, made by Allergan, an AbbVie company) is approved in adults for the temporary improvement in the appearance of moderate to severe lateral canthal lines — one of four cosmetic areas on the label, alongside frown lines, forehead lines and platysma (neck) bands.

FDA added the crow's-feet indication on September 11, 2013.

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.

For this area the injections go into the lateral orbicularis oculi, the muscle that circles the eye.

Cleveland Clinic describes Botox as treating dynamic wrinkles, the lines that show when a muscle contracts — smiling, for this area — and says patients whose wrinkles remain deep even at rest may benefit from adding a dermal filler.

The crow's feet are one entry in the 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 lateral canthal lines.

Whether the treatment fits a particular person — medical history, medicines, how the muscle around the eye 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.

The label also warns — a warning, not an absolute bar — that people with neuromuscular disorders such as myasthenia gravis, Lambert-Eaton syndrome or ALS may be at increased risk of clinically significant effects, and it 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 — a different area — 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.

The labeled dose is 24 units in total: 12 units per side, given as 4 units into each of 3 sites per eye — 6 injection points in all, placed in the lateral orbicularis oculi.

Crow's feet carry a stand-alone labeled dose, set for the area on its own.

When other upper-face areas join the same session, the label's combined totals are 44 units for frown lines plus crow's feet, and 64 units when the forehead is treated too.

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 another brand's dose — and its per-unit price — does not transfer.

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.

A quote built on the labeled 24-unit dose is 24 times the practice's per-unit price; a practice that prices by area quotes the crow's feet as one area.

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 from botulinum toxin 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 crow's feet.

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

Because the label gives no crow's-feet figure, a month count quoted for this area specifically is an estimate, not a label figure.

What changes duration 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 crow's-feet trials also speak to repeat treatment: 1.5% of 916 treated subjects developed binding antibodies, and none developed neutralizing antibodies.

The label says frequent or higher doses may increase antibody formation and recommends the lowest effective dose at the longest feasible interval.

This area has its own row in the trial data.

In the Botox Cosmetic crow's-feet trials, eyelid edema — swelling of the eyelid — was the most common adverse reaction, at 1% of treated subjects against 0% on placebo.

The label also notes reports of dry eye associated with injection in or near the orbicularis oculi, the muscle this area targets.

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.

Who may inject is state law.

The American Med Spa Association (AmSpa) says injecting botulinum toxin is the practice of medicine — a prescription drug being used to affect living tissue — so it belongs to a physician, an independent-practice nurse practitioner or another licensed professional acting 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 — around the eye, in this case.

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, and said the incidents involved injections by licensed and unlicensed individuals in non-medical or unlicensed settings, with product apparently bought from unlicensed sources.

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.