Reviewed by Dr Salinda Johnson MD FSCD
If you are researching “skin quality” treatments in London, you will quickly meet three names: polynucleotides, Profhilo and exosomes. They are often grouped together as biostimulators. They are not the same treatment, they do not suit every face, and they should not be sold as a one-size injectable facial.
This guide is written for patients comparing options at a doctor-led clinic. It explains what each treatment is designed to do, who tends to benefit, and how we decide between them at The London Cosmetic Clinic on Harley Street.
What biostimulators actually do
Dermal fillers add or restore volume. Toxin relaxes overactive muscle. Biostimulators sit in a third group: they aim to improve the quality of the skin — hydration, elasticity, texture and the way light hits the face — by supporting the skin’s own repair processes.
That distinction matters. If the main issue is a deep fold or a hollow temple, filler may still be the honest answer. If the issue is crepey texture, dullness, fine dehydration lines or early laxity, a biostimulator is often the better first conversation.
Polynucleotides: repair and resilience
Polynucleotides are injectable fractions of DNA, typically derived from trout or salmon DNA and highly purified for medical use. In clinic they are used to support tissue repair, calm inflammation and improve skin thickness and elasticity over a course of sessions.
They are often considered when skin looks tired rather than hollow: under-eyes that crease, cheeks that have thinned, necks and décolletage, or skin that has been stressed by acne, procedures or environmental damage. They can also be discussed for selected body areas.
A typical plan is a short course, then review. Results are gradual. That is a feature, not a flaw — you should not walk out looking “done”. You should look like your skin is behaving better.
Profhilo: hydration and skin bounce
Profhilo is a high-concentration hyaluronic acid product designed to spread through the tissue rather than sit as a shaped gel. It is used to improve hydration, firmness and “skin bounce”, most often in the face, and sometimes in the neck or hands.
Profhilo is usually a two-session protocol a month apart, with maintenance later. It is a strong option when the complaint is dull, dehydrated, finely lined skin rather than a specific contour problem.
It is not a substitute for cheek or jawline filler. Patients who want a sharper profile still need a contouring plan, not only a skin-quality plan.
Exosome therapy: skin and hair regeneration
Exosome therapy uses signalling vesicles that cells use to communicate. In aesthetics they are being used to support skin regeneration and, in selected cases, hair quality. The evidence base is newer than Profhilo’s, so a responsible clinic will talk about potential and protocol, not miracles.
Exosomes may be discussed when the goal is recovery and regeneration — after energy-device treatments, for lacklustre skin, or as part of a hair plan — rather than instant plumpness.
Side-by-side: how we choose
| Goal | Often first look at |
|---|---|
| Dehydration, fine creasing, “tired skin” | Profhilo |
| Repair, elasticity, under-eye crepe, stressed skin | Polynucleotides |
| Regeneration, combination protocols, selected hair concerns | Exosomes |
| A fold, hollow or shape change | Dermal filler, not a biostimulator alone |
| Lines from muscle movement | Toxin such as Alluzience |
Many patients do not need only one. A common Harley Street plan is toxin for movement lines, a biostimulator for skin quality, and small-volume filler only where structure is missing.
Can they be combined — and in what order?
Yes, but not on a whim and not all on the same day for every patient. Sequence depends on bruising risk, product behaviour and any energy-device work such as Ultherapy, FaceTite or SkinPen microneedling.
A doctor should map the year, not sell three vials in one sitting because they are fashionable.
Who should not have these treatments
Pregnancy and breastfeeding, active infection in the area, some autoimmune or allergy histories, and unrealistic expectations (“I want a facelift in a syringe”) are common reasons to pause. Under-eye anatomy is unforgiving; not every tear trough is a polynucleotide or filler candidate. That decision belongs in a face-to-face assessment.
What happens at a Harley Street consultation
At The London Cosmetic Clinic you are assessed by a GMC-regulated doctor in a CQC-regulated setting, led by Medical Director Dr Salinda Johnson. We look at skin quality, volume, muscle movement and medical history. You leave with a plan, not a menu.
FAQs
How long do polynucleotides take to work?
Most patients notice a change in skin quality over weeks, not overnight. A course is more important than a single session.
Is Profhilo the same as filler?
No. Profhilo is designed to bio-remodel and hydrate. It is not used to sculpt a cheekbone or lift a fold the way a cohesive filler is.
Are exosomes safe?
Safety depends on the product source, processing and who injects or applies it. Ask what preparation is used and why it was chosen for your indication.
Will I bruise?
Any injectable can bruise. Under-eyes and necks bruise more easily. Plan around events.
Can I have these if I already have filler?
Often yes, but spacing and product choice matter. Tell your doctor everything that has been injected, including elsewhere.
Ready to compare options properly?
Book a consultation at our Harley Street clinic and we will tell you which of these — if any — is the honest next step. Book a consultation · Contact us
