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Mesoestetic

Also known as: mesoestetic, meso estetic, cosmelan

Mesoestetic is a Barcelona-founded professional skincare brand whose UK site lists cosmelan and dermamelan depigmenting methods, mesopeel chemical peels and Class III CE-marked mesohyal intradermal products. Its legal notice identifies Mesoestetic UK & Ireland Ltd as the selling and distribution entity; Companies House records separate UK ownership.

Evidence status

Manufacturer-supported

Dermamelan has one open-label ten-woman pilot reporting improvement, but no indexed clinical study names cosmelan and no indexed record names mesopeel or mesohyal. The company's published depigmentation research is preclinical and company-authored or funded; generic peel and ingredient evidence does not validate the proprietary systems. The official UK site documents the portfolio and distribution, not clinical efficacy.

What Mesoestetic is, and the ranges available#

Mesoestetic Pharma Group s.l. is a Barcelona-based professional skincare manufacturer with in-house biotechnology and medical units. Its official UK professional site lists cosmelan and dermamelan depigmenting methods, mesopeel chemical peels, home-care cosmetics and mesohyal intradermal products. Company employees have published research on candidate depigmenting actives using laboratory models.[6, 7, 20]i[20]

The brand's legal notice identifies Mesoestetic UK & Ireland Limited at Unit 11 Novus Park, Haig Road, Knutsford as the company selling and distributing its products in the UK and Ireland. Companies House records company 13242983 there and Birtwistle Properties Ltd as its sole active person with significant control and owner of at least 75% of shares. The commercial role comes from the legal notice; the ownership record comes from Companies House.[2, 19][2]

A second similarly named active company, Mesoestetic PH Limited, company 14837455, was incorporated in 2023 at the same Knutsford site under the same SIC code. Companies House does not state its relationship to the official partner or the Spanish manufacturer, so the legal party on an account or invoice should be identified from the actual contract.[3]

This entry covers the brand, its product families, UK structure and product-specific evidence. Melasma, hydroquinone, chemical peels, mesotherapy and individual actives are treated separately; this page does not reproduce their class evidence.

Use of Mesoestetic in aesthetic practice#

Cosmelan, dermamelan and mesopeel products are presented as cosmetics. In GB they fall under assimilated Regulation (EC) No 1223/2009, which regulates composition, safety, notification and claims but does not license the person applying a cosmetic. “Professional use” is a manufacturer or distributor designation, not a statutory medical credential.[1, 11, 13]i

Mesoestetic's UK professional site describes mesohyal as Class III CE-marked intradermal medical solutions. That is a manufacturer statement: no public certificate, notified-body dossier or MHRA product record was located to confirm it independently. If it is a device, GB market access falls under the Medical Devices Regulations 2002: UKCA is the enduring route, with CE transition until the sooner of certificate expiry or 30 June 2028 for MDD/AIMDD devices and until 30 June 2030 for EU MDR devices.[12, 20]i

A CE- or UKCA-marked device is not automatically a prescription-only medicine. Conversely, any injectable cocktail containing a POM engages medicines law and a prescriber. No English statutory licensing scheme is in force, but absence of a current licence is not a competence standard. Mesotherapy is not one of the five named JCCP/CPSA register modalities, while peels sit within skin rejuvenation.[11, 12, 17]i[15]

England's 2023 consultation proposed green placement for mesotherapy and epidermal-depth peels, amber for medium-depth peels and red for deeper peels. The August 2025 response, based on 11,848 responses, expressly deferred procedure allocation and announced further work; the tiers remain proposals.[10][11]

Scotland's 2026 Act names injectable procedures and peels penetrating deeper than epidermis in its schedule. Those paragraphs were not in force at Royal Assent and commencement is staged. Wales's statutory special-procedure scheme covers four different procedures and not peels or mesotherapy.[17][18]

Contraindications and cautions#

The contraindications and preparation requirements for the exact Mesoestetic product govern. Cosmelan and dermamelan are multi-active topical systems, mesopeel is a family of chemical peels, and mesohyal is injectable; a brand-wide contraindication list would hide the most important distinctions.

Depigmenting systems require the underlying pigmentation to be identified before product selection. Melasma, post-inflammatory hyperpigmentation, lentigines and suspicious lesions do not share a diagnosis or referral pathway. Current or planned prescription treatment, pregnancy, barrier impairment, active dermatitis, infection and recent procedures are screened against the exact product instructions and the treating professional's competence.

Injectable products create an additional gate: verified device status and intended purpose, lawful supply, sterile handling, anatomy training, emergency preparedness and explicit insurance cover. A cosmetic account or brand certificate does not establish injectable competence.

Published cosmelan ingredient declarations contain retinol, salicylic acid and several depigmenting actives, while third-party lists for cosmelan 2 differ materially by date or pack. Suitability should therefore be based on the current UK pack and manufacturer documentation rather than an online ingredient list.[13]

Clinical uses and the evidence behind them#

Dermamelan for melasma

The only indexed clinical dermamelan study was an open-label 2011 pilot in ten women with Fitzpatrick II–IV melasma. It reported a 50% improvement in MASI after three months of once-daily use and mild irritation as the recorded adverse effect.[4]

The study had no control, randomisation or blinding, ran for four months and included no Fitzpatrick V or VI participants. It cannot separate the product from photoprotection, spontaneous change, regression to the mean or observer expectation. The authors said the result “suggests” rapid improvement rather than establishing efficacy. The funding and conflict statement could not be retrieved; NLM's “Research Support, Non-U.S. Gov't” label is not enough to identify a sponsor.[4][4]

Cosmelan

No indexed clinical study of cosmelan, and no indexed record for mesopeel or mesohyal, was identified. Internal, conference or non-indexed data may still exist.[5]

Claims circulating for cosmelan, including very large spot-intensity outcomes, could not be traced to a retrievable clinical paper. The absence of a public study means a practitioner cannot represent those figures as independently appraised evidence.

Manufacturer laboratory research

Mesoestetic's 2023 and 2024 depigmentation papers used tyrosinase assays, human melanocyte cultures and reconstructed three-dimensional epidermis. They included no participants; the 2024 ethics and consent statements both say “not applicable”. Authors were company employees and the company funded the later work.[6, 7]

These studies can support biological plausibility for the tested candidates. They cannot establish the clinical efficacy, tolerability or recurrence rate of cosmelan or another finished product.

Evidence for the treatment classes

A 2024 review of 24 studies and 1,075 patients found support for chemical peels in melasma, with glycolic acid the best-supported agent. A 2025 network meta-analysis of 14 randomised trials and 738 women compared treatment categories but no proprietary Mesoestetic method.[8, 9]

One declared cosmelan active, hexylresorcinol, has human comparative data. A double-blind split-body trial in 32 healthy women compared 1% hexylresorcinol with 2% hydroquinone for face and hand pigmentation over 12 weeks and found both improved pigmentation without a detected difference. Twenty-nine were analysed; participants did not have diagnosed melasma, the study was not powered to prove equivalence, and cosmelan does not disclose its hexylresorcinol concentration.[16]

The category evidence is relevant but does not validate a proprietary concentration or complete formulation.

Selecting a Mesoestetic product#

Selection first identifies the product category: home-care cosmetic, professional peel or injectable device. The current pack, Responsible Person or device documentation, intended purpose, ingredients, lot and manufacturer instructions govern; an online trade name is not enough.

For cosmelan and dermamelan, product identity matters. Dermamelan's ten-person pilot cannot be cited for cosmelan, and third-party INCI lists for cosmelan 2 differ. Published current lists contain no hydroquinone and include kojic derivatives, hexylresorcinol, retinol, phytic and salicylic acids in cosmelan 1, with azelaic acid, kojic acid, alpha-arbutin, niacinamide and ascorbic acid in one cosmelan 2 record.[4, 13]

Hydroquinone is prohibited in GB cosmetics except at 0.02% after mixing in professional artificial-nail systems. There is no facial or skin-lightening cosmetic exception. A London Trading Standards programme found hydroquinone in 25 of 122 sampled lightening products, making current lawful supply and pack verification more than a theoretical concern.[1][1][14]

For mesohyal, the supplier should provide the certificate, classification, intended purpose, certificate route and expiry, MHRA registration and UK Responsible Person. The current device instructions and named product protocol then govern. Skinipedia does not publish a generic peel, depigmentation or injection protocol.

Adverse effects and their management#

Topical irritation and desquamation

The dermamelan pilot recorded mild irritation. Multi-active depigmenting systems and peels can produce erythema, stinging, desquamation and barrier disruption; the incidence and severity cannot be inferred across products with different compositions.[4, 13]

Pigmentary change and recurrence

Melasma is relapsing and procedure-related inflammation can worsen pigmentation. Class-level peel evidence does not establish how a Mesoestetic system performs in deeper phototypes, and the only dermamelan pilot excluded Fitzpatrick V–VI.[4, 8, 9]

Injectable complications

Adverse effects of injectable mesotherapy depend on the exact product, injection plane, anatomy, sterility and operator competence. Pain, swelling and bruising must be distinguished from infection, vascular compromise, neurological symptoms, allergy or another unexpected reaction. The manufacturer's device vigilance route applies where an incident may involve the product.

Referral and scope boundaries#

Aesthetic depigmentation begins only after presentations requiring medical diagnosis have been excluded. Changing, asymmetric, bleeding or otherwise suspicious lesions, pigment change without a clear benign explanation, treatment-resistant or severe melasma and suspected dermatitis are referred appropriately.

An injectable product or deeper peel is not brought within scope by brand training alone. Where the product contains or is mixed with a prescription medicine, prescribing belongs to an authorised prescriber; where the technique or complication exceeds the practitioner's competence, the client is referred to an appropriately qualified clinician.

Possible hydroquinone adulteration, a mismatch between pack and published ingredients or suspected unlawful product supply should stop use and enter the supplier and regulatory reporting route.[1, 13, 14]

Mechanism of action#

Mesoestetic's depigmentation approach combines multiple pathways rather than one proprietary mechanism. Declared ingredients include tyrosinase-directed actives, retinoids, hydroxy acids, antioxidants and pigment-transfer or inflammatory modulators. Laboratory papers examine candidate activity in enzymes, cultured melanocytes and reconstructed epidermis.[6, 7, 13]

Those models do not establish a patient outcome. The melasma and azelaic acid entries, together with the cited human evidence on hydroquinone and related actives, carry the clinical evidence and limitations.

Commonly misstated claims#

“Cosmelan is clinically proven”

No indexed cosmelan clinical study was located, and the large percentages repeated by clinics could not be traced to a retrievable paper.[5]

Supported statement: cosmelan is a proprietary multi-active depigmenting method whose public ingredient rationale is stronger than its indexed product-level clinical evidence.

“Cosmelan and dermamelan have the same evidence”

The one indexed pilot tested dermamelan in ten women. It did not test cosmelan.[4, 5]

Supported statement: dermamelan has one small uncontrolled pilot; the result does not transfer to cosmelan.

“The products secretly contain hydroquinone”

The located cosmelan ingredient declarations contain no hydroquinone, and the 2011 paper described dermamelan as a non-hydroquinone agent. Hydroquinone skin-lightening cosmetics are prohibited in GB.[1, 13][4]

Supported statement: the published formulations are non-hydroquinone systems; the current UK pack remains the definitive ingredient record.

“Hexylresorcinol is proven equivalent to hydroquinone”

A 1% hexylresorcinol cream produced no detected difference from 2% hydroquinone in a small split-body dyspigmentation trial, but the study did not establish equivalence in melasma and cosmelan discloses no comparable concentration.[16]

Supported statement: 1% hexylresorcinol has comparative human pigmentation data; transfer to cosmelan is unproven.

Areas of remaining uncertainty#

  • Funding and conflicts for the 2011 dermamelan pilot remain unretrievable; this means its commercial provenance cannot be characterised.
  • Unindexed company or non-English cosmelan studies may exist; this prevents turning “not indexed” into “no data anywhere”.
  • Active concentrations and the current UK cosmelan 2 formulation are uncertain because ingredient lists are unquantified and divergent; this limits comparison with ingredient trials.
  • Mesohyal's medical-device class and primary registration record were not confirmed; this means clinics need the current certificate and MHRA documentation from the supplier.
  • The commercial relationship among the Spanish manufacturer and two UK companies is not shown by Companies House; this prevents describing the UK entities as manufacturer-owned or exclusive without a contract.

Frequently asked questions#

Is cosmelan clinically proven for melasma?

No indexed clinical study of cosmelan was located. The best public product-specific evidence is a ten-person uncontrolled pilot of dermamelan, a different method.[4, 5]

Does cosmelan contain hydroquinone?

Not in the located ingredient declarations. Hydroquinone is prohibited in GB facial cosmetics; current pack information should be checked because formulations can change.[1, 13]

Is mesohyal a prescription medicine?

It is marketed as a CE-marked device, not a POM, but the exact classification was not confirmed from a primary record. Any mixture containing a POM is a separate medicines-law question.[12]

Are England's green-tier placements now law?

No. They came from the 2023 consultation. The 2025 response deferred allocation and no scheme is in force.[10, 11]

What protocol should be followed?

The current manufacturer instructions for the exact cosmetic, peel or injectable product govern. Skinipedia does not publish a generic substitute.

References#

Each source is graded by evidence tier. Tier 4 material (manufacturer documents, expert consensus, practitioner experience) is useful for protocol and context, and is never presented as equivalent to independent clinical evidence.

  1. Regulation (EC) No 1223/2009 of the European Parliament and of the Council of 30 November 2009 on cosmetic products, as assimilated law in Great Britain. Annex II (List of substances prohibited in cosmetic products), entry 1339; Annex III (List of substances which cosmetic products must not contain except subject to restrictions laid down), entries 14 and 95.Tier 1Supports: Verified against the legislation.gov.uk text on 1 August 2026. Annex II entry 1339 reads verbatim: '1,4-Dihydroxybenzene (Hydroquinone), with the exception of entry 14 in Annex III', CAS 123-31-9, EC 204-617-8. Annex III entry 14 reads: 'Hydroquinone / Hydroquinone / 123-31-9 / 204-617-8 / Artificial nail systems / 0,02 % (after mixing for use) / Professional use only', with label wording 'For professional use only / Avoid skin contact / Read directions for use carefully'. Annex III entry 95 separately permits Hydroquinone methylether/Mequinol (p-Hydroxyanisol, CAS 150-76-5, EC 205-769-8) at 0,02% after mixing for use, artificial nail systems, professional use, with the same warnings. Scope limits: this establishes that hydroquinone is prohibited in cosmetic products in Great Britain with a single narrow exception for artificial nail systems, and that no skin-lightening use is permitted at any concentration. It says nothing about hydroquinone supplied as a medicine on prescription, which is a separate regime. Version note: legislation.gov.uk serves this instrument at the point-in-time version of 31 December 2020 (end of the implementation period), which is the assimilated text; no later GB amendment to these entries was identified, but the site does not display a post-2020 revision.
  2. Companies House, company profile and persons with significant control: MESOESTETIC UK & IRELAND LIMITED, company number 13242983.Tier 1Supports: Register records, independently re-checked 1 August 2026: company number 13242983; status Active; type Private limited company; incorporated 3 March 2021; registered office Unit 11 Novus Park, Haig Road, Knutsford, Cheshire, England, WA16 8FB; nature of business SIC 47750 - Retail sale of cosmetic and toilet articles in specialised stores; last accounts made up to 30 April 2025, next accounts due 31 January 2027; last confirmation statement 23 January 2026, next due 6 February 2027. The persons-with-significant-control page records '1 active person with significant control / 0 active statements', named as Birtwistle Properties Ltd, Active, notified 3 March 2021, correspondence address Chestnut Tree Farm, Holly Lane, Styal, Cheshire, SK9 4JL, governing law United Kingdom (England And Wales), legal form Corporate, place registered Companies House, company registration number 11711272, incorporated in England And Wales. Nature of control is recorded verbatim as 'Ownership of shares - 75% or more'. Scope limit: the PSC register shows control, not distribution agreements; the register does not disclose any contractual relationship with Mesoestetic Pharma Group s.l., does not record the Spanish manufacturer as a PSC, and Companies House does not verify filed information.
  3. Companies House, company profile: MESOESTETIC PH LIMITED, company number 14837455.Tier 1Supports: Register records, independently re-checked 1 August 2026: company number 14837455; status Active; type Private limited Company; incorporated 1 May 2023; registered office Lindow House Unit 11, Novus Park, Haig Road, Knutsford, Cheshire, United Kingdom, WA16 8FB; nature of business SIC 47750 - Retail sale of cosmetic and toilet articles in specialised stores; last accounts made up to 30 April 2025; last confirmation statement 3 September 2025. Scope limit: the registered office is the same Knutsford site as 13242983 but the address strings are not identical ('Lindow House Unit 11' versus 'Unit 11'), and the register does not state the relationship between the two companies. A third search hit, MESO ESTETIC LTD (10219974, Milton Keynes), appears unrelated to the brand and is not relied on here.
  4. Tsilika K, Levy JL, Kang HY, Duteil L, Khemis A, Hughes R, Passeron T, Ortonne JP, Bahadoran P. A pilot study using reflectance confocal microscopy (RCM) in the assessment of a novel formulation for the treatment of melasma. J Drugs Dermatol. 2011 Nov;10(11):1260-4. PMID 22052305.Tier 3Supports: Citation verified against the MEDLINE record on 1 August 2026: authors, journal, volume 10, issue 11, pages 1260-1264 and PMID all resolve correctly. NLM publication types: 'Clinical Trial', 'Research Support, Non-U.S. Gov't', 'Journal Article'. Open-label trial, no control group, no randomisation, no blinding. Ten women with melasma, Fitzpatrick types II-IV, treated with once-daily Dermamelan for three months within a four-month trial. The objective is stated verbatim as assessing 'the efficacy and safety of a new non-HQ bleaching agent Dermamelan(R) (Mesoestetic, Barcelona, Spain) in the treatment of melasma'. Outcome: 'Based on the MASI score, Dermamelan treatment improved melasma by 50 percent', confirmed on standard and UV-light photography; maximum effect usually reached by one month and maintained one month after completion. Reflectance confocal microscopy at baseline found hyperpigmented keratinocytes in all 10, dendritic cells in 2/10 and melanophages in 2/10; patients with melanophages had a poorer outcome, but not those with dendritic cells. A statistically significant decrease in pigmented epidermal keratinocytes was detected on RCM. 'Mild irritation was the only adverse event observed during treatment.' 'The majority of patients were satisfied with the result.' The authors' own conclusion is hedged: the study 'suggests that Dermamelan produces significant rapid improvement'. Scope limits: n=10, uncontrolled, four-month horizon, no Fitzpatrick V-VI participants, melasma relapse beyond one month not assessed, and no comparator, so photoprotection, regression to the mean and observer expectation cannot be separated from product effect. The study tests dermamelan, not cosmelan.Funding / interest: No funding statement or competing-interests declaration could be retrieved. The article is paywalled, the publisher's article page returned HTTP 404 on 1 August 2026, and Europe PMC returns grantsList null and conflictOfInterestStatement null for PMID 22052305. Countervailing signal: NLM assigned the publication type 'Research Support, Non-U.S. Gov't', which indicates the indexers saw an acknowledgement of non-US-government research support in the full text; that is inconsistent with the paper carrying no support statement at all, but it neither confirms nor excludes commercial sponsorship by Mesoestetic, and no such statement is retrievable. The only listed affiliation is the Department of Dermatology, University Hospital of Nice, France.
  5. NCBI PubMed records for the terms 'cosmelan', 'dermamelan', 'mesopeel', 'mesohyal' and 'mesoestetic'. Accessed 1 August 2026.Tier 4Supports: Results as returned by the API, reproduced on re-execution. 'cosmelan'[All Fields]: count 1, sole hit PMID 30000902, which is the LactMed monograph 'Lanolin' and is not a study of the product; 'cosmelan AND melasma': count 0. 'dermamelan'[All Fields]: count 1, PMID 22052305 (the 2011 pilot). 'mesopeel': count 0, returned with the term flagged as a phrase not found in the index. 'mesohyal': count 0, same. 'mesoestetic'[All Fields]: count 17. All 17 were individually resolved by esummary and inspected: six are preclinical or laboratory papers with Mesoestetic Pharma Group authorship (PMIDs 42113675, 40806676, 40026043, 39598529, 36682042, 33901008), one is an editorial profile of a Mesoestetic scientist (36696544), one is the 2011 dermamelan pilot (22052305), and the remaining nine are unrelated papers - senescence biology, cancer biology, metabolomics, melanoma AI, filler case series and consensus reviews - in which 'mesoestetic' appears only in a competing-interests declaration. Two of the nine were checked directly to exclude an over-debunk: PMID 41541242 (HA-CaHA hybrid filler, 25 Chinese patients) names Mesoestetic only as a source of honoraria to an author, and PMID 32440186 (Sinclair-related consensus review) names Mesoestetic only as personal fees to Dr Sabine Zenker. Neither studies a Mesoestetic product. Scope limits: PubMed indexes only journals it lists, so this does not exclude evidence in non-indexed journals, conference abstracts, industry white papers or non-English literature; it does establish that no indexed clinical trial of cosmelan, mesopeel or mesohyal exists under those product names.
  6. Martinez-Gutierrez A, Perez-Martinez M, Pena-Rodriguez E, Gomez-Escalante S, Luis LGS, Gonzalez MC. Depigmenting topical therapy based on a synergistic combination of compounds targeting the key pathways involved in melasma pathophysiology. Exp Dermatol. 2023 May;32(5):611-619. doi:10.1111/exd.14752. PMID 36682042.In vitroTier 3Supports: Entirely preclinical, no human participants. Artificial-intelligence-driven modelling selected a retinol + diosmin + ferulic acid combination. An in vitro cellular tyrosinase activity assay showed a synergistic depigmenting effect; the combination downregulated ET-1 and COX-2 gene expression and IBMX-induced dendricity in human melanocytes, upregulated IL-1b, TIMP3 and several endogenous antioxidant enzymes, and reduced melanin levels in a phototype VI 3D reconstructed epidermis model. Scope limits: cell culture and reconstructed-epidermis models only; no patients, no clinical endpoint, no MASI, no in vivo safety data. The combination described is not stated to be the cosmelan or dermamelan formulation. Citation note: the author names in the original package were transcribed with forenames and surnames inverted (for example 'Alfredo MG' for Martinez-Gutierrez A) and have been corrected against the MEDLINE record.Funding / interest: All six authors are affiliated to the Biotechnology Unit or the Medical Unit of Mesoestetic Pharma Group, Barcelona. The commercial interest is direct and disclosed in the author affiliations, and NLM assigned the publication type 'Research Support, Non-U.S. Gov't'. The article is not deposited in PMC and no separate funding or competing-interests statement was retrievable on 1 August 2026.
  7. Martinez-Gutierrez A, Bertran A, Noya T, Pena-Rodriguez E, Gomez-Escalante S, Pascual S, Luis LS, Gonzalez MC. New Chalcone-Derived Molecule for the Topical Regulation of Hyperpigmentation and Skin Aging. Pharmaceutics. 2024 Oct 31;16(11):1405. doi:10.3390/pharmaceutics16111405. PMID 39598529, PMC11597169.In vitroTier 3Supports: Preclinical, no human participants; the paper's own Institutional Review Board Statement and Informed Consent Statement both read 'Not applicable.' Homology modelling built a 3D structure of human tyrosinase and virtual docking predicted binding; the synthesised chalcone-derived molecule inhibited human tyrosinase and melanin synthesis in 2D monoculture and in a phototype VI reconstructed human pigmented epidermis model, modulated melanogenesis-related miRNAs, and showed anti-glycation, antioxidant, mitochondrial-protection, autophagy-activation and wound-healing activity. Skin irritation was assessed on MatTek reconstructed human epidermis (EPI-200-SIT) under OECD Test Guideline 439, not on people. Conclusion wording, both versions recorded to avoid understating the paper: the abstract calls the molecule 'a potential candidate to be used as a depigmenting and anti-aging agent', while the paper's Conclusions section states it 'is a promising candidate to be used as an effective depigmenting and anti-aging agent with suitable properties to be introduced in dermatology and cosmetics formulations'. Scope limits: no clinical efficacy, no patient safety data, and the molecule is not identified as an ingredient of any marketed cosmelan or dermamelan product.Funding / interest: Declared verbatim in the Conflicts of Interest section: 'All authors were employed by the company Mesoestetic Pharma Group s.l. The research was funded by Mesoestetic Pharma Group s.l.' The Funding section reads: 'The research was funded by Mesoestetic Pharma Group s.l.' Europe PMC records the sole grant agency as 'Mesoestetic Pharma Group s.l.'
  8. Sarkar R, Lakhani R. Chemical Peels for Melasma: A Systematic Review. Dermatol Surg. 2024 Jul 1;50(7):656-661. doi:10.1097/DSS.0000000000004167. PMID 38530985.Tier 1Supports: Citation verified 1 August 2026. PubMed-based systematic review of prospective case series of more than 10 cases and RCTs. 24 studies included, total sample size 1,075, study duration 8 to 36 weeks. All studies used self-assessment, physician global assessment and MASI. Conclusion verbatim: 'Chemical peels were found to be safe and effective in the management of melasma', with 'glycolic acid was found to be the most safe and effective in melasma'. Scope limits: the authors state a meta-analysis could not be done because of heterogeneity, so no pooled effect size exists. No proprietary or branded depigmenting method was among the reviewed interventions; this supports peels as a class, not any Mesoestetic product.
  9. Leung JH, Leung HWC, Wang S-Y, Jang Y-C, Chan ALF. Efficacy and Safety of Different Treatments for Melasma: Network Meta-Analysis of Updated Data. Diseases. 2025 Sep 25;13(10):316. PMID 41149049.Tier 1Supports: Citation verified 1 August 2026; PMID 41149049 added, which was missing from the original package. Network meta-analysis of 14 RCTs, 738 women, 15 treatment modalities, ranked by mean difference in MASI. Highest-ranked were intradermal PRP, intradermal PRP plus oral tranexamic acid, and intradermal TXA plus Q-switched laser, followed by other combination regimens. Topical triple combination cream was 'comparable to that of HQ4% alone for the treatment of MASI'. Authors conclude 'the optimal new treatment strategy for melasma may be a multimodal approach, including effective photo-protection and a combination of different treatment modalities'. Scope limits: 738 participants across 15 modalities means thin networks and wide uncertainty; several highest-ranked options are injectable or prescription-only and several involve hydroquinone, which is not lawfully available in GB cosmetics. No cosmelan, dermamelan or other proprietary depigmenting method was evaluated. Declared verbatim: 'This research received no external funding'; 'The authors declare no conflicts of interest'.
  10. Department of Health and Social Care. The licensing of non-surgical cosmetic procedures in England: consultation document. Consultation open 2 September 2023, closed 28 October 2023.Tier 1Supports: Re-read in full 1 August 2026. This is the only document that assigns individual procedures to the proposed green/amber/red tiers, and it is a consultation proposal, not law. Green tier verbatim: 'microneedling, mesotherapy, intense pulsed light (IPL) and light emitting diode (LED) therapies, chemical peels that involve destruction only into viable epidermis (the outermost layer of the skin)', continuing with no-needle fillers, micropigmentation, non-ablative laser hair removal and photo rejuvenation. Amber tier includes 'medium depth peels that involve full thickness destruction of entire epidermis into upper dermis', alongside botulinum toxin injections, semi-permanent dermal fillers injected into the face only, biorevitalisation and hyaluronic acid injections, vitamin and mineral injection procedures, and 'POM treatments applied topically for cosmetic purposes, such as prescription strength vitamin A and hydroquinone'. Red tier includes 'deeper chemical peels such as phenol peels' and lasers targeting the deeper dermis. Mesotherapy appears in the green list only, and in no other tier. Scope limits: England only; a proposal; superseded on tier placement by the 2025 response, which defers assignment.
  11. Department of Health and Social Care. The licensing of non-surgical cosmetic procedures in England: consultation response. Published 7 August 2025.Tier 1Supports: Quotations re-verified against the page text 1 August 2026. 'We received 11,848 responses to the online consultation.' The response explicitly does not assign procedures to tiers: 'While we recognise the desire for clarity and certainty within the sector, further work is required to determine where specific procedures will sit in the proposed tiering system and to determine which practitioners should be permitted to carry out certain procedures.' It states 'we are not proposing at this stage to remove any of the procedures currently included within the scope of the licensing scheme or associated regulation, nor are we proposing to add any further procedures', and commits to a further consultation: 'The proposed changes will be detailed in a public consultation, to be launched early next year.' Priority is given to legislation ensuring 'those procedures deemed to pose the highest level of risk (including procedures aimed at augmenting the breast, buttocks and genitals with dermal fillers) can only be performed by suitably qualified regulated healthcare professionals working for CQC-registered providers'. Scope limits: England only; no scheme is in force; parliamentary time is still required; the phrase 'early next year' is not dated in the document and its meaning relative to the August 2025 publication date is ambiguous.
  12. Medicines and Healthcare products Regulatory Agency. Regulating medical devices in the UK (guidance). GOV.UK.Tier 1Supports: Re-verified 1 August 2026. Great Britain devices are governed by the UK Medical Devices Regulations 2002, which transposed the EU AIMDD (90/385/EEC), MDD (93/42/EEC) and IVDD (98/79/EC). The MHRA designates and monitors UK approved bodies and conducts market surveillance. UKCA marking is the route to the Great Britain market. CE-marked devices are accepted in Great Britain during transition: devices compliant with the EU MDD or AIMDD 'can be placed on the Great Britain market up until the sooner of expiry of certificate or 30 June 2028', and devices compliant with the EU MDR 'up until 30 June 2030'. Scope limits: Northern Ireland follows the EU MDR/IVDR and requires CE marking; UKCA is not recognised in the EU or Northern Ireland; the guidance sets out product-placing rules and says nothing about which practitioner may administer a device to a patient. Critically for this entry, the guidance does not identify any Mesoestetic product; it describes the regime that would apply if a given mesohyal product is in fact a medical device, which could not be confirmed from a primary manufacturer or MHRA registration source.
  13. INCIDecoder product ingredient records for Mesoestetic Cosmelan 1 Facial Mask (uploaded 6 April 2024), Mesoestetic Cosmelan 2 (uploaded 10 June 2021) and Mesoestetic Cosmelan 2 Cream (uploaded 26 April 2021), each transcribed by third parties from product packaging.Tier 4Supports: All three records retrieved and compared 1 August 2026. Cosmelan 1 Facial Mask declared INCI, in order: Aqua, Glyceryl Stearate, Glycofurol, PEG-75 Stearate, PEG-8, Glycereth-26, Kojic Dipalmitate, Kaolin, Octyldodecanol, Euphorbia Cerifera Cera, C12-15 Alkyl Benzoate, Ethoxydiglycol, Hexylresorcinol, Salicylic Acid, PPG-15 Stearyl Ether, Glyceryl Behenate, Dihydroxychalcone Sulfonic Acid, Hesperidin, Magnesium Ascorbyl Phosphate, Retinol, Retinyl Palmitate, Phytic Acid, Apigenin, Phloretin, Tocopheryl Acetate, Mannitol, Phosphatidylcholine, Cholesterol, Glycerin, Polysorbate 80, Polysorbate 20, Xanthan Gum, Poloxamer 338, Silica Dimethyl Silylate, Pentaerythrityl Tetra-Di-T-Butyl Hydroxyhydrocinnamate, PPG-12/SMDI Copolymer, Simethicone, Butylated Hydroxytoluene, BHA, Phenoxyethanol, Sodium Metabisulfite, Methylparaben, Propylparaben, Ethylparaben, Parfum, Caramel. 'Mesoestetic Cosmelan 2' declared INCI, in order: Aqua, Caprylic/Capric Triglyceride, Azelaic Acid, Aloe Barbadensis Leaf Juice, Sodium Ascorbyl Phosphate, Titanium Dioxide, Glycerin, Kojic Acid, Poloxamer 407, Glyceryl Stearate, Ethoxydiglycol, Hydroxypropyl Starch Phosphate, Alpha-Arbutin, Butylene Glycol Dicaprylate/Dicaprate, Cyclomethicone, Ethylhexyl Methoxycinnamate, Niacinamide, Di-C12-13 Alkyl Malate, Ceteareth-25, PEG-8 Beeswax, Stearic Acid, Tocopheryl Acetate, Retinyl Palmitate, Dimethicone, Alcohol, Behenyl Alcohol, Disodium Ethylene Dicocamide PEG-15 Disulfate, Citric Acid, Ascorbic Acid, Bisabolol, Salicylic Acid, Sclerotium Gum, Sorbitan Stearate, Stearyl Dimethicone, Sodium Lauroyl Lactylate, Aminoethylphosphinic Acid, Rumex Occidentalis Extract, Acacia Senegal Gum, Glyceryl Stearate Citrate, Glycyrrhiza Glabra Root Extract, Allantoin, Sodium Metabisulfite, Butylene Glycol, Phytic Acid, Xanthan Gum, Phenoxyethanol, Manganese Oxide, Tocopherol. Hydroquinone appears in none of the lists. Important discrepancy found on verification: a separate INCIDecoder record, 'Mesoestetic Cosmelan 2 Cream', carries a materially different and much shorter declaration - Aqua, Titanium Dioxide, Octyl Methoxycinnamate, Cetearyl Alcohol, Sodium Lauryl Sulfate, Sodium Cetearyl Sulfate, Paraffinum Liquidum, Kojic Acid, Butyl Methoxydibenzoylmethane, Phytic Acid, Ascorbic Acid, Retinyl Palmitate, Ceteareth-12, Parfum, Methylchloroisothiazolinone, Methylisothiazolinone - with no azelaic acid, no alpha-arbutin and no niacinamide. Scope limits: these are third-party transcriptions of consumer packs, not manufacturer regulatory documents; INCI lists are qualitative and give no concentrations; the two divergent Cosmelan 2 records demonstrate directly that pack versions and reformulations differ, so no single list can be taken as the current UK-market formulation. Date correction: INCIDecoder displays upload dates in MM/DD/YYYY (confirmed by a sibling record dated 04/26/2021), so the Cosmelan 1 record dated 04/06/2024 was uploaded 6 April 2024, not 4 June 2024 as originally stated. Mesoestetic's own sites (mesoestetic.com, mesoestetic.co.uk) returned HTTP 403 to automated retrieval on 1 August 2026, re-confirmed on verification, so the primary manufacturer listing could not be read directly.
  14. London Trading Standards. Skin lightening products project (2014-15 sampling programme and subsequent enforcement).Tier 4Supports: Figures re-verified 1 August 2026. 122 products purchased from London shops and health and beauty salons were tested. 'Of 122 samples, 25 (20.5%) contained hydroquinone.' Separately, and on a different denominator, 'from 87 samples, 33 (37.9%) contained mercury of which 14 (16% of total) were found to have significantly high levels'. Enforcement outcome: 'thousands of products were subsequently seized and prosecutions followed. Over £100,000 in fines and costs were imposed by the Courts as well as suspended prison sentences.' The Cosmetic Products Enforcement Regulations 2013 are cited as the enforcement instrument, carrying up to one year's imprisonment and a fine of up to £20,000. Scope limits: London only, sampling a decade old, and deliberately targeted at the illicit skin-lightening market rather than at professional-channel brands; it says nothing about Mesoestetic products and is cited only to establish that hydroquinone adulteration in the UK depigmentation market is an enforced reality rather than a theoretical concern.
  15. Joint Council for Cosmetic Practitioners. Treatments (public information page listing the procedural modalities recognised by the JCCP register, each with a linked Cosmetic Practice Standards Authority standard).Tier 2Supports: Retrieved 1 August 2026. Verbatim: 'The JCCP currently recognises the following five procedural modalities that are performed by our Registrant Practitioners:' followed by Botulinum Toxins; Dermal Fillers; 'Skin Rejuvenation - Micro Needling and Peels'; 'Lasers and Light (LIPLED)'; Hair Restoration Surgery. Each modality carries its own linked 'CPSA Standard'. The page adds: 'These procedural modalities are simply the treatments that we regulate currently according to a set of prescribed practice standards (as determined by the Cosmetic Practice Standards Authority) and formal educational qualifications that are set down by the JCCP.' The word 'mesotherapy' does not appear anywhere on the page. Scope limits: this is the JCCP's own public-facing register scope, not statute and not a competence framework document; it establishes which modalities the JCCP registers and standard-sets for, and that mesotherapy is not one of them, but it does not itself state that no competence standard for mesotherapy exists anywhere.
  16. Prospective, randomized, double-blind clinical study of split-body comparison of topical hydroquinone and hexylresorcinol for skin pigment appearance. Arch Dermatol Res. 2023 Jul;315(5):1207-1214. doi:10.1007/s00403-022-02514-0. PMID 36502500.Tier 2Supports: Added on adversarial verification; the original package asserted that no such head-to-head trial existed. NLM publication type 'Randomized Controlled Trial'. Thirty-two healthy female participants aged 35-65 (mean 50.93 +/- 7.37), Fitzpatrick skin types I-IV, randomised to topical 1% hexylresorcinol or 2% hydroquinone applied twice daily to the left or right side of the face and the corresponding hand for 12 weeks; 29 completed. Colorimetric measurements of forehead, cheeks and hands plus standardised photography and clinical grading at baseline, week 4 and week 12. Result verbatim: 'Pigmentation measured by colorimeter and clinical grading were significantly decreased at 4 and 12 weeks relative to baseline with no difference between the HR and HQ groups. No adverse effects were noted with either intervention.' Scope limits, which matter: the population is healthy volunteers with general dyspigmentation and cosmetic concern about skin tone, NOT diagnosed melasma; MASI was not used; n=29 analysed is small for an equivalence claim and the study is not powered as a non-inferiority trial, so 'no difference' is absence of a detected difference, not demonstrated equivalence; the comparison is 1% hexylresorcinol against 2% hydroquinone, and the concentration of hexylresorcinol in the cosmelan mask is not disclosed, so this cannot be read across to the product. No funding or competing-interests statement was retrievable from the abstract record.
  17. Non-surgical Procedures and Functions of Medical Reviewers (Scotland) Act 2026 (2026 asp 13), schedule 1 and section 24(2).Tier 1Supports: Retrieved 1 August 2026. The Bill was passed by the Scottish Parliament on 17 March 2026 and received Royal Assent on 12 May 2026. Schedule 1 ('Specified non-surgical procedures', introduced by section 1(1)(a)(ii)) names, among others: 'Ablative laser treatment'; 'Chemical peel - A procedure (a) in which a chemical is used to remove skins cells in the area of treatment, and (b) which penetrates deeper than the epidermis'; 'Dermal microcoring'; 'Injectable procedure - A procedure other than tattooing in which a substance is injected (including by means of a microneedle) into or under skin for a cosmetic or wellbeing purpose (or both)'; 'Intravenous procedure'; 'Microneedling'; and procedures carried out with a prescribed anaesthetic or on an intimate area by reference to the Civic Government (Scotland) Act 1982 (Licensing of Non-surgical Procedures) Order 2026 (S.S.I. 2026/87). Every schedule 1 paragraph carries the commencement note 'not in force at Royal Assent, see s. 24(2)', and the schedule is displayed as prospective. A Commencement No. 1 and Saving Provision instrument exists (S.S.I. 2026/206 (C. 21)), so parts of the Act are being brought into force in stages. Scope limits: Scotland only; the schedule 1 procedures are not yet in force; the Act as drafted prohibits provision of specified procedures to under-18s and outside permitted premises rather than creating a practitioner competence regime; and a chemical peel is only within schedule 1 if it penetrates deeper than the epidermis, which is precisely the classification question cosmelan raises.
  18. Public Health (Wales) Act 2017 (anaw 2), section 57 'What is a special procedure?'. In force 29 November 2024 by S.I. 2024/1248.Tier 1Supports: Section 57 names exactly acupuncture, body piercing, electrolysis and tattooing as special procedures. Chemical peels and mesotherapy are not among those four. Wales only.
  19. Mesoestetic UK. Legal Notice, sections 1–2. Accessed 4 August 2026.Tier 4Supports: The legal notice names MESOESTETIC E-COMMERCE, S.L. as owner of mesoestetic.co.uk and states that Mesoestetic UK and Ireland Limited, at Unit 11 Novus Park, Haig Road, Knutsford WA16 8FB, is the entity 'providing the service of selling and distributing mesoestetic products in UK and Ireland' and managing the ecommerce store. This directly establishes the UK entity's selling and distribution role; Companies House separately establishes company number, filings and ownership.Funding / interest: Brand-controlled commercial website for the UK and Ireland partner. It establishes identity and positioning, not independence or clinical efficacy.
  20. Mesoestetic UK professional product pages: cosmelan system, dermamelan, mesopeel and mesohyal ranges. Accessed 4 August 2026.Tier 4Supports: The official UK professional site presents cosmelan and dermamelan as depigmenting methods, mesopeel as professional chemical peels and mesohyal as 'intradermal medical solutions'. Its mesohyal and medical-aesthetics pages describe the range as Class III CE-marked. Scope limit: these are manufacturer claims. No public certificate, notified-body dossier or MHRA product record was supplied on the pages, so the Class III/CE description is not independently verified.Funding / interest: Manufacturer-controlled professional product pages. Commercial source; useful for current portfolio and claimed classification, not proof of clinical performance or regulatory conformity.