Last updated: October 2026.
Botox lasts approximately three to four months, and it starts working faster than most pages admit. The prescribing information describes the injected muscles beginning to relax one to two days after injection, with the effect increasing in intensity through the first week.
Both halves of that timeline get misreported constantly, usually in the direction of making you wait longer than you need to and then expect the result to fade sooner than it does. Below is what the labels actually say, what genuinely shortens your result, and whether Botox really stops working over time. For treatment itself, see Botox and dermal fillers in Midtown Manhattan.
Key Takeaways
- Three to four months is the duration in the label, measured on the frown lines.
- One to two days to begin working, building through the first week.
- Two weeks before you judge the result or book around an event.
- Every three months at most. Closer intervals have not been studied.
- It does not stop working. Neutralizing antibodies appeared in none of 916 patients.
- Botox, Dysport and Xeomin last about the same. The label ranges overlap.
How Long Does Botox Last?
The prescribing information states that the duration of effect for glabellar lines is approximately three to four months.
One detail in that sentence matters and almost never gets mentioned. Three to four months is the figure for the frown lines between the brows. The label gives no duration statement at all for crow’s feet, forehead lines or platysma bands, which means the number everyone quotes for every area was measured on one area.
In practice the upper face behaves fairly consistently, so three to four months is a reasonable expectation across it. The honest framing is that it is a well-supported estimate for one region and a sensible assumption for the others, rather than a figure the label stands behind everywhere.
Within that window, the fade is gradual rather than sudden. Movement returns bit by bit as nerve endings re-establish signalling, so most people notice the lines beginning to appear with expression before they look like they did before treatment.
When Does Botox Kick In?
Earlier than the commonly repeated three to five days. The label describes botulinum toxin inducing “chemical denervation of the injected muscles one to two days after injection, increasing in intensity during the first week.”
So the sequence is: something by day two for many people, a clear change through the first week, and a settled result after about two weeks. That last figure is the one to plan around, because it is when you can judge what you actually got.
If you are treating ahead of a wedding, a shoot or anything else with a date attached, book at least two weeks out. That leaves room to assess the result and adjust it if one side has responded differently from the other, which is a normal thing to need and a simple thing to fix.
Judging your result on day four is the most common mistake patients make. It reliably produces a worried phone call about an outcome that is still developing.
The Week-by-Week Timeline
| When | What is happening |
|---|---|
| Days 1 to 2 | Chemical denervation begins. Some people notice movement softening |
| Days 3 to 7 | Effect increases in intensity. The visible change arrives here |
| Around day 14 | Settled result. Judge it now, and raise any asymmetry |
| Months 1 to 3 | Stable effect |
| Months 3 to 4 | Movement gradually returns as signalling re-establishes |
| Month 3 at the earliest | Soonest a repeat treatment has been clinically evaluated |
Nothing in that sequence requires you to change what you do, beyond the first few hours of aftercare. Those rules sit with the dosing detail in our guide to Botox units and aftercare.
Botox vs Dysport vs Xeomin: Does One Last Longer?
This gets asked constantly and the labels give a duller answer than the marketing does.
| Product | Duration in the label | Onset in the label |
|---|---|---|
| Botox Cosmetic | Approximately 3 to 4 months, frown lines | Denervation at 1 to 2 days, building through week one |
| Dysport | “May last up to four months” | Not stated as a median in the label |
| Xeomin | Typically up to 12 to 16 weeks | Median within 2 to 7 days |
Twelve to sixteen weeks is three to four months. Up to four months is the same ballpark. On duration, the three products are not meaningfully different, and a provider telling you one lasts substantially longer is going beyond what the labelling supports.
What does differ is formulation. Xeomin is described in its label as yielding the active neurotoxin “without accessory proteins,” meaning it carries none of the complexing proteins the others include. That difference is sometimes offered as a reason it might provoke fewer antibodies, which leads directly into the next section.
One thing that genuinely does not transfer between these products is units. A unit of one is not a unit of another, and comparing per-unit prices across brands tells you nothing.
What Shortens Your Result
Several things plausibly affect how long an individual result holds. Being honest about which are well established and which are reasonable inference is more useful than a confident list.
- Dose. The best-supported factor. An underdosed area runs out sooner, which is why a cheap treatment often turns out not to be cheaper per month.
- How strong and active the muscle is. A powerful, frequently used muscle recovers function sooner than a weaker one.
- Treatment area. Small, mobile areas such as around the mouth typically hold for less time than the frown lines.
- Exercise and metabolic rate. Commonly cited and plausible, though not something the labelling addresses. Treat it as a pattern injectors observe rather than an established figure.
- Smoking and sun exposure. These accelerate skin ageing generally. Whether they shorten the neuromodulator effect specifically is a weaker claim than it is usually presented as.
What will not extend your result is treating more often. That approach runs into the interval limit below and carries its own downside.
Does Botox Stop Working Over Time?
This is the most common worry about long-term use, and the data does not support it.
Across three lateral canthal line trials covering 916 treated patients, 14 patients (1.5%) developed binding antibodies, which do not block the effect. None of the 916 developed neutralizing antibodies, the kind that would. In the Xeomin glabellar trials, none of 464 patients developed neutralizing antibodies either, and Dysport’s glabellar data reports the same.
The label goes further on sustained effectiveness, noting that the response rate for forehead lines “was similar across all treatment cycles.” Repeat treatment did not produce a weakening response.
There is a real caveat attached. The label states that “botulinum toxin injections at more frequent intervals or at higher doses may lead to greater incidence of antibody formation,” and that the risk “may be minimized by injecting with the lowest effective dose given at the longest feasible intervals between injections.”
So the answer is that Botox does not stop working, but chasing a shorter interval or a bigger dose is the one approach that moves you toward the outcome you were worried about. When someone says their Botox stopped working, underdosing or a change in injector is a far likelier explanation than resistance.
How Often Should You Get Botox?
Every three to four months, and no sooner than three.
Both the Botox and Dysport labelling set that floor explicitly. Botox states that dosing more frequently than every three months has not been clinically evaluated, and its medication guide puts it plainly: it is not known whether the product is safe and effective used more than once every three months. Dysport states it should be administered no more frequently than every three months.
A practice willing to re-treat you at six or eight weeks is operating outside what the evidence covers, and doing the one thing associated with antibody formation.
Scheduling on the natural cycle, which for most people means three or four treatments a year, keeps the result continuous without ever shortening the interval.
Frequently Asked Questions
How long does Botox last?
The prescribing information puts the duration of effect for frown lines at approximately three to four months. Worth knowing: that figure is specific to the glabellar lines between the brows, and the label gives no duration statement for crow’s feet or forehead lines. In practice those areas behave similarly.
When does Botox kick in?
Sooner than most pages say. The label describes chemical denervation of the injected muscles beginning one to two days after injection, increasing in intensity during the first week. So you may notice something by day two, but the first week is when the change becomes obvious.
How long does it take Botox to work fully?
Allow two weeks before judging the result. The effect builds in intensity through the first week and settles after that. If you are treating ahead of an event, book at least two weeks out so there is room to assess and adjust if needed.
Does Botox stop working over time?
The evidence says no. In the lateral canthal line trials, none of 916 patients developed neutralizing antibodies, and 1.5% developed binding antibodies that do not block the effect. The label also reports that the response rate for forehead lines was similar across all treatment cycles.
Which lasts longer, Botox, Dysport or Xeomin?
The labels do not support a meaningful difference. Botox states approximately three to four months for frown lines, Dysport says the effect may last up to four months, and Xeomin gives a typical duration of 12 to 16 weeks. Those ranges overlap almost completely, so pick on other grounds.
How often should you get Botox?
No more often than every three months. Both the Botox and Dysport labels are explicit: dosing more frequently than every three months has not been clinically evaluated. More frequent treatment is also the condition most associated with antibody formation, so closer scheduling works against you.
What to Do Next
How long your own result holds depends mostly on the dose your anatomy needs, which is an assessment rather than a guess. You can request a consultation or read about our injectable treatments. For dosing by area, see our guide to how many units of Botox the forehead needs.
Individual results vary. This article is general information, not medical advice or a diagnosis, and it does not replace the prescribing information or a consultation with a qualified injector.
Sources
- Allergan. BOTOX Cosmetic (onabotulinumtoxinA) for injection, full prescribing information. Duration and onset of effect, immunogenicity, dosing interval. Read the label on DailyMed
- Merz Pharmaceuticals. XEOMIN (incobotulinumtoxinA) for injection, full prescribing information. Description, duration and onset of effect, immunogenicity. Read the label on DailyMed
- Ipsen. DYSPORT (abobotulinumtoxinA) for injection, full prescribing information. Duration of effect, retreatment interval, immunogenicity. Read the label on DailyMed
