Wrinkles: Crow’s Feet, Frown & Forehead Lines

Everyone who makes facial expressions develops some dynamic lines eventually; this is a normal part of having an expressive face. What varies is how early and how deep they become, and the evidence points to several contributing factors working together:

• Environmental: UV exposure, pollution and smoking all accelerate the underlying skin change.
• Genetics and skin type: some people etch lines more readily than others for reasons that are largely inherited.
• Behavioural: habitually expressive movement patterns (frequent squinting, frowning) drive more muscle activity over time.
• Intrinsic ageing: a gradual, genetically programmed process that compounds everything above.

Because the muscle-contraction component and the deeper collagen/elastin-loss component are mechanistically different, a purely dynamic line (visible only when you move) and a deeply etched, static line (visible at rest) don’t always respond to treatment the same way: see the treatment section below.

Anti-wrinkle injections are a prescription-only medicine in the UK. This is not marketing language; it is a legal and regulatory fact, confirmed by the UK’s medicines regulator, which has explicitly warned that if you’re offered treatment without a proper medical consultation, in an informal setting, or at a price well below the usual rate, that should be treated as a warning sign. It can only be prescribed following a face-to-face consultation with an appropriately qualified prescriber such as a doctor, and the prescriber is responsible for ensuring whoever actually gives the injection is trained and safe to do so.

Ptosis (a drooping eyelid or eyebrow) is the most common complication of frown-line treatment, and this should be said plainly rather than glossed over. It happens when the medicine diffuses slightly beyond the intended muscle. A large real-world safety analysis of aesthetic anti-wrinkle treatment found that facial paresis, ptosis or asymmetry accounted for around one in ten of all reported adverse events: the single largest complication category identified, out of tens of thousands of reports spanning more than two decades.

The same analysis found serious systemic complications to be rare overall, supporting a generally favourable safety profile when treatment is given appropriately, but ptosis specifically is common enough that you should expect it to be discussed with you before treatment, not discovered afterward. When it occurs, it typically appears within one to two weeks, peaks around two weeks, and usually resolves on its own within three to four months as the effect wears off.

A “frozen” or unnatural look is a real risk of overdosing or poor technique, and one reason technique and dosing judgement matter as much as the medicine itself.

Realistic expectation: anti-wrinkle injections treat the muscle-contraction component of a line. A line that has become deeply etched and is visible even at rest may need additional treatment (such as skin resurfacing or filler) alongside toxin, not instead of it.