Botox FAQ: myths and facts

Some questions about botulinum toxin come up again and again, and the answers that circulate are sometimes approximate, or even wrong. We take them one by one, separating what the official labels and publications say from what is a matter of medical opinion. For the basic concepts, start with our page on what botulinum toxin is and how it is used.

Does Botox necessarily freeze your face?

Not necessarily. The toxin reduces the contraction of the injected muscles; how strong that effect is depends on the dose, the number of injection points and the muscles chosen^1,2. An expert consensus stresses the importance of a prior aesthetic assessment and of tailoring treatment area by area⁸. A frozen look usually reflects a stronger effect than intended, and it is temporary. No study, however, can guarantee a "natural" result: this is a point to discuss with your doctor.

Can you become resistant to botulinum toxin?

It is possible, but rare. The body can produce antibodies that reduce or cancel the effect of the toxin⁵. Closely spaced injections and high doses make them more likely^1,5. In the trials of the short-acting botulinum toxin (serotype E), none of the patients tested developed neutralising antibodies, but data are still limited². The best way to limit this risk is to respect the intervals set between two sessions.

Is Botox permanent?

No, the effect is always temporary. With a type A toxin, it usually lasts 3–4 months, and up to 6 months for some products^1,9. With the short-acting botulinum toxin, it usually lasts 2–3 weeks². As of 9 October 2026, this toxin is approved in the European Union (since 15 July 2026) and in Canada (since 22 June 2026), for frown lines only^10,11. The details are on our page explaining why the effect of the toxin fades over time.

Can you stop the injections?

Yes, at any time. There is no obligation to continue. When the effect fades, the nerve ending recovers its ability to control the muscle, which gradually regains its strength^2,7. Lines caused by movement then reappear at the same pace, and the face gradually returns to how it looked before treatment.

Does your face age faster when you stop?

We found no reliable source showing this. What is known is that the effect of the toxin is reversible and that the muscle gradually recovers its activity^2,7. The face therefore gradually regains the movement it had before treatment. The idea of accelerated ageing after stopping, like that of a long-term protective effect, is not demonstrated by the sources we consulted.

Can a disappointing result be corrected?

It depends on the problem. An insufficient effect or a slight asymmetry can sometimes be touched up, once the peak effect has been reached, at the doctor’s discretion. An excessive effect, such as a drooping eyelid or eyebrow, is temporary and fades as the nerve recovers⁷; depending on the problem, the doctor may sometimes suggest a measure to ease it in the meantime. After a short-acting toxin, a type A toxin injected less than 30 days later has not been evaluated². The SOS section of the site details each problem, area by area.

Can the toxin be removed or dissolved?

No, not once it is working. No product can dissolve or cancel a botulinum toxin that has already bound. Once it has entered the nerve ending, it can no longer be reached by the antibodies that could neutralise it⁶. An unwanted effect therefore disappears as the nerve recovers⁷. With the short-acting toxin, whose effect usually lasts 2–3 weeks, this recovery is faster², but that changes nothing for a type A injection already given.

Why does the toxin sometimes not work?

Several causes are described in the labels. In case of failure, they ask doctors to look at the choice of muscles injected, the injection technique, a dose that is too low or, more rarely, the formation of antibodies^3,4. The labels also state that these products must be stored in a refrigerator⁹. Before concluding that it has failed, you also need to wait for the peak effect, which may only be reached at day 30 with some type A toxins^3,4.

Can you have an injection before a wedding?

Yes, provided you plan ahead. It all depends on the timings: with a type A toxin, the peak effect is reached between week 2 and week 4^1,3; with the short-acting toxin, around day 7, for a duration of 2–3 weeks². Leaving some margin is useful to judge the result, and the choice is discussed with your doctor. Our page on how fast each type of toxin takes effect details these timings for both families, without recommending one over the other.

Can you switch botulinum toxins?

Yes, but not just any way. The doctor chooses the product. The units of one toxin are not interchangeable with those of another: the dose has to be recalculated^2,4. The effect of different serotypes given a short time apart is unknown¹, and a type A toxin injected less than 30 days after the short-acting toxin has not been evaluated². Always mention your last injection and, if possible, the product used.

Are all toxins the same?

No, they are not interchangeable. Each product has its own label, its own dosing unit, its own indications and sometimes its own age limits^2,3,4. For example, they are not all approved for the same areas: depending on the product, a type A toxin may also be approved for crow’s feet, or for crow’s feet and the forehead^1,4. The short-acting toxin stands out for a faster onset and a shorter duration². None is better in absolute terms: the choice is made in consultation, and the precautions to take before and after an injection apply whatever the product.