A dermal filler is a gel, usually cross-linked hyaluronic acid, injected to restore volume, rebuild structural support or refine a contour. It works by occupying space and attracting water. Most are reversible with an enzyme. In the UK they are regulated as medical devices rather than as medicines.
| Classification | Medical device. No prescription required in the UK |
|---|---|
| Material | Cross-linked hyaluronic acid in almost all cosmetic use |
| Areas | Temples, cheeks, tear troughs, nose, chin, jaw, folds, lips, hands |
| Result | Immediate, with swelling settling over one to two weeks |
| Duration | Roughly six to eighteen months depending on product, site and movement |
| Reversal | Hyaluronidase, which is itself a prescription-only medicine |
| Serious risk | Vascular occlusion, including rare visual loss in high-risk areas |
Manufacturers vary three things when they design a gel: how heavily the hyaluronic acid is cross-linked, the size and uniformity of the particles, and the concentration. The result is a family of products with genuinely different physical behaviour.
Placing the wrong gel in the wrong plane is the mechanism behind most poor results. A firm product placed superficially reads as a ridge or casts a grey shadow through thin skin. A soft product placed deep where support was needed simply disappears.
The question worth asking is not which brand, but which plane, and why that product for that plane.
The face does not age by the skin loosening alone. Fat compartments deflate and slide downward, the bone of the eye socket and jaw resorbs, and the ligaments tethering soft tissue give way. The visible result appears lower down than the cause.
So the fold beside your mouth is frequently a cheek problem, the shadow under your eye is frequently a mid-face problem, and the softness along your jaw is frequently a chin problem. A practitioner who treats only the spot you pointed at will produce a heavier face rather than a refreshed one.
In the UK, dermal fillers are regulated as medical devices. There is no prescription requirement and, at the time of writing, no general licence needed to inject them. A person with no clinical training can lawfully buy filler and inject your face. Legislation enabling a licensing scheme for non-surgical cosmetic procedures in England exists but has not been brought into force.
In London there is one additional layer worth knowing about. Most London boroughs licence premises offering certain treatments under local special treatment provisions, which sets standards for the premises rather than for the clinical judgement of the person working in it. It is worth asking whether the premises holds a licence, and it is not a substitute for checking the individual.
Hyaluronidase dissolves hyaluronic acid filler and is the emergency treatment when a blood vessel is compromised. It is a prescription-only medicine, so a practitioner without prescribing rights cannot lawfully hold it. Ask whether it is on the premises today, who prescribed it and who would administer it. There is no acceptable answer involving tomorrow morning.
This is the complication that justifies every check in this guide. If filler enters an artery, or compresses one, the blood supply to the tissue that artery feeds is interrupted.
Managed promptly with hyaluronidase, it usually resolves without lasting damage. Left alone, it can cause skin death and permanent scarring.
Filler forced backwards through vessels connected to the eye can cause sudden visual loss. The highest-risk sites are the glabella between the brows, the nose and the tear trough. Any vision change after facial filler is an emergency and needs immediate medical attention as well as contact with the practitioner.
This is why nose reshaping with filler deserves particular thought. It is frequently marketed as a lunchtime procedure. It is the highest-risk site on the face.
The clinic guide covers verification, and what treatment costs explains why comparing quotes by millilitre is the wrong measure.
Roughly six to eighteen months for hyaluronic acid, depending on the product, the site and how much the area moves. Static areas such as the cheek last longest.
Hyaluronic acid filler can be dissolved with hyaluronidase. This is a strong reason to choose a hyaluronic acid product and a practitioner who can prescribe.
It carries the highest vascular risk of any common filler site, including the rare risk of visual loss. It should be treated as a serious intervention rather than a quick appointment.
There is no answer before an assessment. Any figure quoted before someone has examined your face is a sales estimate.
Sensible volumes replacing lost structure do not. Repeated overfilling beyond what the tissue originally held is a different matter.
Severe or increasing pain, blanching then mottling of the skin, coolness, or any change in vision. Contact the practitioner immediately and seek urgent care for vision changes.
No. Filler supports and replaces volume. Significant laxity is a different problem and needs a different conversation, sometimes a surgical one.
Treatment
The highest-leverage area on the face, and the easiest one to ruin by degrees.
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Treatment
Small volumes, thin skin, high stakes. The area where patient selection matters most.
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Treatment
Definition comes from proportion. Frequently the chin is the answer, not the jaw.
ReadThis website sells nothing and books nothing. It exists so that you walk into a consultation already knowing which questions separate a careful practitioner from a confident one, and already knowing when the correct answer is to leave without treatment.
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.