
Botulinum toxin type A temporarily reduces the nerve signal reaching the small muscles it is placed into. Those muscles contract less, so the skin folded by them creases less. It is a prescription-only medicine, it takes several days to appear, and it wears off over a few months.
| Classification | Prescription-only medicine. Must be prescribed for you individually |
|---|---|
| Usual areas | Frown lines between the brows, forehead lines, lines at the outer eye |
| Other uses | Jaw muscle reduction, neck bands, a modest brow lift, excessive sweating |
| Onset | Change from about day three, settled at two weeks |
| Duration | Typically three to four months |
| Downtime | None, beyond the possibility of small bruises |
| Reversibility | None. It cannot be undone, only waited out |
Muscle contracts when a nerve terminal releases acetylcholine into the gap between nerve and muscle. Botulinum toxin type A prevents that release at the specific points where it is injected. Contraction weakens, and the skin folded by that contraction creases less deeply. The effect is confined to the tissue immediately around the injection, and it is temporary: the nerve grows new terminals over the following months.
Three practical consequences follow. It works on lines caused by movement, not on lines etched into the skin at rest. It takes days rather than minutes to appear. And placement matters more than product, because a millimetre in the wrong direction changes which muscle receives the dose.
Nothing is added to your face. A muscle is asked to work less, and the skin above it stops being folded so often.
There is a persistent belief that a fully immobilised forehead is the sign of a good treatment. It is the sign of a simple one. Removing all movement is straightforward. Reducing movement by a considered proportion, keeping the ability to raise the brows and express surprise while softening the lines that bother you, requires knowing which fibres to treat, at what depth, and which to leave entirely alone.
This is the reason the assessment matters. A face that lifts its brows constantly to keep heavy eyelid skin out of the way is a face that will look worse, not fresher, if the forehead is fully relaxed. A brow that already sits low needs a different plan from a brow that sits high. None of that can be judged from a photograph or a phone call.
Botulinum toxin is a prescription-only medicine in the United Kingdom. It must be prescribed for a named individual by a qualified prescriber: a doctor, a dentist, an independent nurse prescriber or a pharmacist independent prescriber. The professional regulators have been clear that prescribing for cosmetic injection without assessing the person face to face is not acceptable practice.
Advertising a prescription-only medicine to the public is separately prohibited under the Human Medicines Regulations 2012. That is why a clinic operating properly does not publish a brand name beside a price, and why this page does not name a product.
Who is prescribing my medicine, and will they assess me in person today? If the answer involves a form, a video call or somebody who is not in the building, the arrangement is not one the regulators consider acceptable.
Since October 2021 it has been a criminal offence in England to administer botulinum toxin or cosmetic filler for cosmetic purposes to anyone under eighteen, or to make arrangements for it. That applies to every clinic in London.
There is effectively no downtime. Small raised bumps at the injection points settle within the hour. Bruising is possible and more likely if you take anticoagulants, fish oils or high-dose vitamin E, or if you have had a drink shortly beforehand.
The two-week review exists because no face is symmetrical and no first dose is perfect. A small adjustment then is ordinary practice. Ask before you book whether review and adjustment are included, because when they are charged separately the incentive runs the wrong way. Full guidance is on the aftercare page.
Common and minor: pinpoint bleeding, small bruises, a mild headache for a day or two, and a heavy or tight sensation while the effect settles.
Worth understanding in advance:
Suspected side effects can be reported by patients as well as clinicians through the MHRA Yellow Card scheme.
London has more practitioners per square mile than anywhere else in the country and an unusually wide range of standards among them. The checks are specific rather than general:
The London clinic guide explains how to verify each of these at source.
Movement usually begins to change around day three, with the settled result at about two weeks. Judge it at the fortnight, not before.
That is a decision about dose, and you should state your preference clearly. Keeping natural movement while softening lines is achievable and is the harder skill.
Movement returns to exactly where it was and the lines return to how they were. They do not deepen because of treatment.
Advertising a prescription-only medicine to the public is prohibited under the Human Medicines Regulations 2012. Cost can be discussed inside a consultation, which is a different situation.
Practitioners decline cosmetic treatment in pregnancy and breastfeeding because there is no safety evidence to support it.
Repeated cosmetic use over many years is common and generally well tolerated. Sensible practice is the smallest effective dose at the longest interval that keeps you satisfied.
Frequently, because they solve different problems. Muscle movement and lost volume are not the same finding.

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hello@aestheticlaunchlab.comEnquiries are read and answered by Aesthetic Launch Lab, the UK aesthetics digital specialist that operates this website. Please do not send clinical details or photographs. If something has gone wrong after a procedure, contact the practitioner who treated you, or NHS 111, rather than waiting for a reply here.