How long does Botox take to work, and how long does it last?
Neuromodulators do not work on the day of treatment. In clinical studies the first change appears within days and the full effect develops over the following weeks. It then fades gradually over a period of months that differs by product and by person. The figures below come from FDA prescribing information and peer-reviewed studies, and they describe study populations, not a promise for any one patient.
Why nothing happens on the day
A neuromodulator does not relax a muscle the way an anesthetic numbs one. The toxin has to bind to the nerve endings in the injected muscle, be taken inside them, and then cleave a protein the nerve uses to release acetylcholine, the signal that makes the muscle contract. That process takes time, which is why the first change appears over days rather than in the chair.
When it starts to work
The product labels measure “onset” as the first day on which a meaningful share of treated people are rated as responders.
- Botox Cosmetic. in the Botox Cosmetic glabellar line studies, 74% of treated subjects were rated as responders by investigators at day 7, against 6% with placebo (source, verified ). by day 30, 80% of treated subjects were responders, against 3% with placebo (source, verified ). a 2023 review of the Botox glabellar line program describes improvement by day 7 and a peak effect between 30 and 60 days (source, verified ).
- Dysport. a 2020 systematic review of 42 publications found Dysport's onset most often reported within 2 to 3 days, and as early as 24 hours in two studies (source, verified ). How Botox and Dysport compare.
- Daxxify. in Daxxify's two pivotal trials the median onset of a one-point improvement was 3 days (source, verified ).
- Xeomin. Xeomin's label reports its upper facial line trial results at day 30 after treatment and gives no earlier onset figure (source, verified ).
So for most people, something is visible within the first week and the full effect arrives over the following weeks. Judging the result at day two is judging it too early.
How long it lasts
“How long it lasts” has more than one meaning. Studies measure the time until lines are no longer rated none or mild, the time until they return to how they were before, or simply the longest point at which a difference from placebo was still measurable. The figures below say which.
- Botox Cosmetic. in the Botox Cosmetic glabellar line studies the severity of lines was reduced for up to 120 days (source, verified ). the median duration of response was 120 days for glabellar lines on frowning and 139 days for lines visible at rest (source, verified ).
- Dysport. the Dysport label says its clinical effect may last up to four months, and that repeat dosing in clinical studies showed continued efficacy over up to four repeated treatments (source, verified ). the systematic review found Dysport's duration most often reported as four months (18 studies), with a range of 3 to 6 months across studies; the review was sponsored by Dysport's manufacturer (source, verified ).
- Daxxify. in Daxxify's pivotal trials and in the 2,691-subject open-label SAKURA 3 study, the median time until glabellar lines were no longer rated none or mild was 24.0 weeks after a 40 Unit treatment, and the median time to return to baseline in SAKURA 3 was 28.0 weeks (source, verified ). subjects in Daxxify's glabellar line trials were followed through at least week 24, and the label itself states no median duration (source, verified ).
- Xeomin. The label reports its upper facial line results at day 30 and does not state a duration figure for those areas.
How often it can be repeated
Every label sets a floor on the interval between treatments.
Minimum interval: the Botox Cosmetic label states that dosing more often than every 3 months has not been clinically evaluated (source, verified ). Dysport should be administered no more frequently than every three months (source, verified ). Xeomin retreatment should be given no more frequently than every three months (source, verified ). Daxxify should be administered no more frequently than every three months for any indication (source, verified ).
That floor is a safety limit, not a schedule. Many people are treated less often than the minimum allows, and the right interval for you is the one at which movement has returned enough that you want it softened again.
Why your result may differ
The figures above are medians and responder rates from trial populations, measured in particular muscles at labeled doses. “Up to 120 days” is the longest point at which the Botox studies still found a difference from placebo, not a typical result. A median of 24 weeks means half the people in the Daxxify trials kept their rating for less time than that.
Three things change the picture for an individual. The muscle treated: the trial figures for every product are for the frown lines between the brows, and other areas were studied less or not at all. The dose: a conservative first treatment is deliberately lighter than a labeled study dose might be. And the comparison itself: these products have not been tested against one another in a single trial at matched doses, so the differences between the lists above are not head-to-head results. One of the reviews cited, on Dysport, was sponsored by its manufacturer; this is noted on the claim.
What wearing off looks like
The effect fades the way it arrived: gradually. Movement returns over weeks, and the lines return toward how they looked before treatment. The effect is temporary by design, and nothing is left behind in the tissue. When to repeat is a decision made with Tanya at a follow-up visit, inside the interval the label allows. The patient guide to neuromodulators.
Sources
- BOTOX Cosmetic (onabotulinumtoxinA) for injection, Prescribing Information (revised 10/2024) , AbbVie Manufacturer Accessed
- DYSPORT (abobotulinumtoxinA) for injection, Prescribing Information (revised 1/2023) , U.S. Food and Drug Administration Regulator Accessed
- XEOMIN (incobotulinumtoxinA) for injection, Prescribing Information (revised 06/2026) , U.S. Food and Drug Administration Regulator Accessed
- DAXXIFY (daxibotulinumtoxinA-lanm) for injection, Prescribing Information , DailyMed, U.S. National Library of Medicine Regulator Accessed
- Treatment of glabellar lines with Botox (onabotulinumtoxinA), Development, insights, and impact , Medicine (PubMed Central) Peer-reviewed Accessed
- Onset and Duration of AbobotulinumtoxinA for Aesthetic Use in the Upper Face, A Systematic Literature Review , Journal of Clinical and Aesthetic Dermatology (PubMed Central) Peer-reviewed Accessed
- DaxibotulinumtoxinA for Injection for the Treatment of Glabellar Lines, Efficacy Results From SAKURA 3 , Dermatologic Surgery (PubMed Central) Peer-reviewed Accessed
Questions readers ask
Can I make it work faster?
There is no established way to shorten onset. You may be told to move the treated muscles for a while after treatment; the product labels do not address this one way or the other. The practical advice is to give it the first week before judging.
When should I book a follow-up?
After the full effect has developed, not in the first few days. The studies measured their main results around a month after treatment, which is also when a small adjustment, if any, can be judged fairly.
Why did my last treatment seem to wear off sooner?
Several things can differ between visits, including the dose, the muscles treated and how the result was judged. Bring the dates and, if you know them, the product and units from previous treatments, so the plan can be compared and adjusted.
Does Daxxify always last six months?
No. The six-month figure is a median from its trials, so half of subjects kept a none-or-mild rating for less than that and half for longer. It was measured with the labeled 40 Unit dose for frown lines, and it has not been compared head to head with the other products in the same trial.
Will I feel it wearing off?
Usually it is seen rather than felt. Movement returns gradually over weeks, and the lines return toward how they looked before. There is no sudden change.
Does it last longer the more treatments I have?
The labels report continued effect over repeated treatment cycles rather than a longer duration with each one. Some people describe longer intervals over time; the trial data above do not measure that, so treat it as an observation, not a finding.
Revision history (1)
- update First version, written from FDA prescribing information and peer-reviewed literature Editorial team