Switching products is a common question, especially since a new generation of botulinum toxin arrived. It follows on from our comparison of botulinum toxins: here, we do not compare the products with each other, we look at what the official labels say about moving from one to another. The choice of product remains a medical decision, made with you during a consultation.
Why do people switch toxin?
The reasons vary. Your doctor may prefer one product for a given area, because the approved indications are not the same from one product to another. Your age may matter: some type A toxins are only indicated in adults under 654. You may also want a different profile, faster and shorter or slower and longer-lasting, now that a short-acting botulinum toxin (serotype E) is approved in the European Union for frown lines1. As of 9 October 2026, it is also approved in Canada (since 22 June 2026)7. Finally, an effect felt to be too weak sometimes leads to considering another product.
In every case, a few rules written in the labels apply.
Doses do not carry over from one product to another
Each botulinum toxin has its own unit of measurement. The labels make this clear: the units of one product are not interchangeable with those of another, because the methods used to measure potency differ1,3. A dose that works with one toxin says nothing about the dose needed with another.
This is one reason why the choice of product and dose lies with the doctor, and why it helps to know which product you received last time. The labels also ask that the name and batch number of the product administered be clearly recorded1: ask for them at each session.
Between two type A toxins
The type A toxins approved for aesthetic use share the same mode of action, but they are distinct medicines. Their labels all require an interval of at least 3 months between two treatments2,3,4,5. Changing product from one session to the next does not remove this interval: it is for the doctor to set the new dose and the timing of the session.
Onset times also differ slightly from one product to another. According to the labels, the peak effect is seen during the second week5 or around day 304. A result that seems different after switching product is therefore not necessarily a worse result: it may simply develop at a different pace.
Two toxins are not combined
Switching toxin means replacing one product with another, not adding them together. The labels point out that excessive muscle weakness may be made worse by giving another botulinum toxin before the effects of the previous one have resolved1,2. The label of the short-acting toxin states that the effect of giving toxins of different serotypes at the same time is unknown, and that giving it at the same time as another botulinum toxin has not been studied and must be ruled out1.
In practice, always mention a recent injection, even one given by another doctor or for another reason, a medical one for example.
Before the short-acting botulinum toxin
The short-acting toxin is only approved for vertical lines between the eyebrows, in adults, when they have an important psychological impact1. Other areas, such as the forehead or crow’s feet, are not part of this indication1. Switching toxin for an area other than frown lines is therefore not an option with this product.
Its label provides for occasional use, because of its rapid onset and short duration1. It sets no specific interval to respect after a type A toxin: it only recalls the risk of worsening muscle weakness if the effect of the previous toxin has not resolved1.
After the short-acting botulinum toxin
The effect of the short-acting toxin usually lasts 2–3 weeks1. Its label states that administration of a type A toxin less than 30 days afterwards has not been evaluated1. In a phase 1 study involving 90 people, a type A toxin injected on day 30 had a similar effect whether the participants had received the short-acting toxin or a placebo1.
Repeat injections of the short-acting toxin less than 6 weeks apart have not been evaluated either, nor have more than three consecutive injections beyond 18 weeks1. These limits describe what has been studied, not a recommendation: the schedule is built with the doctor. The trial results and their limitations are presented on our page about studies of the new botulinum toxin.
Switching because the toxin no longer works?
A toxin sometimes seems to lose its effectiveness. One possible cause is the formation of antibodies that neutralise the toxin. This remains rare; a literature review links it mainly to shorter intervals between injections, booster injections and higher doses6. One label also points out that doses given too often can increase this risk3.
Other explanations exist and need to be examined: one label lists the choice of muscles injected, the injection technique and an insufficient dose among the causes of failure to be analysed2. Switching product is therefore not the automatic answer: it is one possible conclusion, after examination.
What to tell your doctor
Before a session with a new product, or with a new doctor, have the following ready:
- the name of the product you received last time, the date and, if possible, the batch number1;
- the areas treated and the result obtained, including an effect that was too weak or too strong;
- any toxin injection received since, whatever the reason1,2;
- your current medicines and medical history, detailed on our page about the precautions before a botulinum toxin injection.
Key points
- The units of one toxin are not interchangeable with those of another1,3.
- Between two type A toxin sessions: at least 3 months, even when changing product2,3,4,5.
- Two toxins are not combined: they must not be given at the same time1.
- After the short-acting toxin, a type A toxin injected within 30 days has not been evaluated1.