Botox before an event: when should you have the injection?

You have a date in mind, a wedding, a photo shoot, an important meeting, and you are wondering when to have a botulinum toxin injection. The answer depends on the family of toxin, because the two approved families do not follow the same timeline. This page describes both, without recommending one over the other; the new botulinum toxin has its own overview page, with its indications and limits.

Two toxins, two timelines

To choose a date, you need to tell three moments apart: when the first effects appear, when the effect peaks, and how long the effect holds before it wears off.

The long-acting toxin (type A)

With the type A toxins approved for aesthetic use, first effects usually appear within 2 to 3 days^3,4, and one product information states that the effect usually appears within one week⁶. The peak effect is reached, depending on the product, during the second week⁵ or around day 30^3,4: the usual way to put it is "between week 2 and week 4"^3,5. The effect then usually lasts 3 to 4 months^4,6, and up to 6 months depending on the product⁷.

In practice, this toxin calls for planning ahead, but once it has reached its peak its effect comfortably covers the period of the event. Why the effect always wears off in the end is explained on the page about how long botulinum toxin lasts.

The short-acting toxin (serotype E)

With the short-acting botulinum toxin (serotype E), clinical effects begin to show 8 hours after injection, the peak effect is seen around day 7, and recovery generally occurs within 2 to 3 weeks¹. In a phase 2b trial, at the highest dose, 41.9% of patients responded to treatment at 24 hours, compared with 93.3% on day 7²: the effect is visible early in some patients, but it is not complete before a week.

In practice, this toxin has a short window of effect: too early, and the effect may have worn off; too late, and it will not yet be at its peak. It is approved only for frown lines in adults¹. It has been approved in the European Union since 15 July 2026 and in Canada since 22 June 2026^8,9.

These timelines, and how to read them, are explained in detail on the page about how long botulinum toxin takes to work.

Work it out from the date of your event

Enter the date of your event: for each of the two toxins, the calculator shows the usual state of the effect on that day, depending on when the injection was given. The timeline lets you switch from one toxin to the other to compare the same steps.

Week-by-week markers

No product information gives a timeline "before an event": the markers below are derived from the official timelines of the two toxins^1,3,4. They describe a usual situation; everyone responds at their own pace.

One month before

With a type A toxin, the peak effect, reached between week 2 and week 4^3,5, should be in place on the day, with time for a check-up with your doctor. With the short-acting toxin, whose effect usually lasts 2 to 3 weeks¹, the effect will probably have worn off by the day.

Three weeks before

For type A toxin, the day falls within the usual period of peak effect^3,5. For the short-acting toxin, the effect may have worn off or nearly so, since it usually fades within 2 to 3 weeks¹.

Two weeks before

With type A toxin, the effect is present, but its peak, reached between week 2 and week 4 depending on the product, may not have arrived yet^3,5. With the short-acting toxin, the peak has passed, since it occurs around day 7, and the effect will probably be declining¹.

One week before

With type A toxin, the effect is usually present, its first signs appearing within 2 to 3 days^3,4, but it is often not yet at its peak. With the short-acting toxin, the peak effect, seen around day 7, usually coincides with the day¹.

A few days before

With type A toxin, the effect may not be visible yet, since its first signs can take up to a week to appear⁶. With the short-acting toxin, the effect will be present, since it begins from 8 hours, but not yet at its peak¹.

The day before

With type A toxin, the effect will usually not be visible yet, first effects appearing within 2 to 3 days^3,4. With the short-acting toxin, the effect will be starting, but it will be far from its peak¹. In both cases, injection-site reactions may still be visible on the day.

Why leave a margin?

A result can only be judged once the peak effect has been reached. And it may turn out not to be what you expected: the product information of the short-acting toxin mentions, for example, a drooping eyelid or eyebrow and an upward lift of the outer end of the eyebrow, which were uncommon or rare in the trials¹; type A toxins also have side effects described in their product information^3,4. These situations fade as the effect of the toxin wears off, so not overnight. Our section on problems after a botulinum toxin injection describes them one by one, with the signs that should prompt you to see a doctor.

The product information also limits quick corrections. For type A toxins, it requires at least 3 months between two sessions^3,4 and does not describe any short-term touch-up: a check-up with your doctor remains possible, but a closely spaced new injection is not documented. After the short-acting toxin, a type A toxin injected less than 30 days later has not been evaluated¹: if the result is not what you expected shortly before the event, no quick correction is therefore provided for.

This is why, if it is your first injection, it is wise to talk to your doctor well ahead of the date: they can tell you whether an injection is suitable, and when.

Injection-site reactions

A botulinum toxin injection can cause pain, swelling, redness or a small bruise at the injection site¹. These matter if the event is the next day, for example for a photo. Tell your doctor about any blood-thinning medicine: one product information calls for caution in patients taking anticoagulants⁴. Never stop such a medicine without the advice of the doctor who prescribed it.

Before any injection

Whatever the date, an injection remains a medical procedure, with its contraindications and precautions, to be reviewed with your doctor. For the short-acting toxin, for example, injection is contraindicated in case of a disease affecting muscle activity in a generalised way or infection or inflammation at the injection site, and its use is not recommended during pregnancy or breastfeeding¹. Also mention any recent injection of another botulinum toxin.

The product information asks patients to seek immediate medical care if they have difficulty swallowing, speaking or breathing after an injection¹.