The professional skincare encyclopedia
Skinipedia,by MSTA.
Every treatment, condition, ingredient, device and brand in professional skincare, explained properly. Written and clinically reviewed by working practitioners, for the people who actually perform these treatments.
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63 entries live · 0 in writing
Conditions
- Acne vulgarisAcne vulgaris is a chronic inflammatory disorder of the pilosebaceous unit, involving follicular hyperkeratinisation, sebum production, Cutibacterium acnes and innate immune activation. It presents as comedones, papules, pustules, nodules or cysts, most often on the face, chest and back.
- Eczema (Atopic Dermatitis)Atopic dermatitis, also called atopic eczema, is a chronic relapsing itchy inflammatory skin disease diagnosed on clinical criteria, involving epidermal barrier dysfunction and immune activation. It is a medical diagnosis made by a clinician, not a skin type, a dryness state, or a condition treatable in a beauty setting.
- HyperpigmentationHyperpigmentation describes skin that appears darker than its surrounding baseline. It is a sign, not one diagnosis: melasma, post-inflammatory hyperpigmentation and solar lentigines have different patterns and causes, while a suspicious or uncertain focal pigmented lesion needs medical assessment first.
- Impaired skin barrierImpaired skin barrier is descriptive shorthand for reduced barrier function, not a validated diagnosis. Dryness, scaling, stinging or raised TEWL may accompany it, but none confirms it alone. Dermatitis, infection, rosacea and sensitive-skin syndrome each require their own assessment.
- Keratosis PilarisA common, benign disorder of the hair follicle presenting as rough keratotic papules, often with perifollicular erythema, on the outer upper arms, thighs, buttocks and cheeks. Harmless and usually asymptomatic; its significance is cosmetic and psychosocial rather than medical.
- MelasmaMelasma is a chronic, relapsing hyperpigmentation disorder causing symmetrical, irregular brown or grey-brown facial patches. Ultraviolet and visible light, hormonal influences and genetic susceptibility contribute, but its biology extends beyond excess melanin and no treatment reliably prevents recurrence.
- Post-inflammatory hyperpigmentation (PIH)Post-inflammatory hyperpigmentation is acquired darkening that remains after skin inflammation or injury. Increased epidermal melanin appears brown, while pigment released into the dermis can appear grey-brown or blue-grey and usually resolves more slowly.
- RosaceaRosacea is a chronic inflammatory condition of the central face. Two features are independently diagnostic: persistent centrofacial erythema with periodic intensification, and phymatous change. Flushing, telangiectasia, inflammatory lesions and ocular signs are not individually diagnostic.
Treatments
- BioRePeelBioRePeelCl3 FND is a branded, two-phase professional peel marketed by CMed Aesthetics as a topical medical device containing 35% trichloroacetic acid. No peer-reviewed clinical trial of the product was located, so its efficacy, penetration depth and product-specific adverse-event profile remain unestablished.
- Chemical peelGuideA chemical peel is the controlled wounding of the epidermis, and sometimes the dermis, with a chemical agent. Peels are classified by the depth of that wound — superficial, medium or deep — which determines the indication, the downtime, the risk and the training required.
- Comedone ExtractionComedone extraction is the mechanical expression of the impacted keratin-sebum plug from a blocked pilosebaceous follicle, using a loop extractor and, for closed comedones, a fine needle or lancet to pierce the surface first. It empties existing lesions; it does not alter follicular hyperkeratinisation.
- DermaplaningGuideDermaplaning is manual exfoliation with a sterile blade held at an angle to the skin, removing stratum corneum and vellus hair. It gives immediate smoothness. Claims beyond that rest on a literature a published systematic review called scarce, anecdotal and not well documented.
- Facial Lymphatic DrainageA manual technique using light, rhythmic, skin-stretching strokes in a set sequence to move interstitial fluid through the superficial lymphatic vessels of the face and neck toward the submental, submandibular, preauricular-parotid and deep cervical node groups.
- Jessner's solutionJessner's solution is 14% resorcinol, 14% salicylic acid and 14% lactic acid in ethanol. It is used alone as a superficial peel and as the keratolytic step before 35% TCA. The modified formula removes resorcinol and adds citric acid.
- LED light therapyGuideThe use of specific wavelengths of light to influence cellular activity in the skin, also called photobiomodulation. Red, blue and near-infrared wavelengths are used for different indications, commonly as a recovery or adjunct treatment.
- MicrodermabrasionA mechanical resurfacing procedure in which abrasive crystals, a diamond-coated tip or a water-and-serum jet are drawn across the skin under vacuum to abrade the stratum corneum. Cosmetic treatment usually removes part of this dead layer, although controlled work shows full-thickness removal is possible at moderate settings.
- MicroneedlingGuideMicroneedling is a treatment creating controlled micro-injuries in the skin with fine needles, intended to trigger the wound-healing cascade and collagen synthesis. Depth, density and passes are selected by indication and anatomical site. Also called collagen induction therapy.
- PolynucleotidesPolynucleotides are sterile, purified DNA fragments — often extracted from fish sperm in aesthetic products — injected intradermally for skin-quality aims. Regulatory classification is product-specific: the cited Plinest range is presented by its manufacturer as CE-marked Class III devices, not licensed medicines.
- Radiofrequency microneedlingGuideRadiofrequency microneedling combines microneedling with radiofrequency energy delivered through the needles, producing mechanical micro-injury plus controlled dermal heating. Because radiofrequency has no chromophore target, its heating is unaffected by skin colour.
- Skin Boosters (Injectable HA)Skin boosters are injectable products placed intradermally or in superficial tissue to spread rather than create projected volume. Named products discussed here are supplied as hyaluronic-acid medical devices for skin-quality claims, but exact formulation, intended purpose, classification and Great Britain market route must be verified product by product.
- TCA peelA trichloroacetic acid peel destroys tissue by protein denaturation. Full-field use is commonly 10–35%; modern medium-depth technique uses an epidermolysis step then 35% TCA. High concentrations are focal techniques — CROSS, for individual atrophic scars — not stronger versions of a field peel.
Devices & Technology
- Cryotherapy (Skin)Controlled destruction of skin tissue by freezing. A cryogen — usually liquid nitrogen or pressurised nitrous oxide — cools tissue until ice forms inside and around cells, killing them by mechanical rupture, osmotic injury and vascular stasis. It destroys tissue; it does not diagnose it.
- DermaluxDermalux is a UK-made family of LED phototherapy devices from Aesthetic Technology Ltd. Its systems deliver blue 415 nm, red 633 nm and near-infrared 830 nm light, singly or in combination. Brand-specific clinical evidence is sparse; most wavelength evidence comes from other devices.
- HydraFacialHydraFacial is a brand of powered hydradermabrasion device made by Hydrafacial LLC, part of SkinHealth Systems Inc. A motorised handpiece pulls a vacuum through a disposable spiral tip while pumping solution onto the skin, combining wet exfoliation, suction extraction and topical delivery in one pass.
- IPL (intense pulsed light)GuideA broadband light technology using filtered wavelengths to target chromophores such as melanin and haemoglobin. IPL is used for pigmentation, vascular concerns and hair reduction, and requires careful Fitzpatrick assessment.
- Laser ResurfacingA controlled thermal injury delivered by a laser whose wavelength is absorbed by tissue water, either vaporising the epidermis and upper dermis (ablative) or heating the dermis while leaving the epidermis intact (non-ablative), applied confluently across the surface or as microscopic treatment zones.
- Morpheus8A branded bipolar fractional radiofrequency microneedling platform made by InMode Ltd, delivering 1 MHz RF through detachable single-use tip heads of 12, 24 or 40 pins at selectable depths. Its FDA clearance is for coagulation/contraction of soft tissue and haemostasis, not for any cosmetic outcome.
- Radiofrequency (Non-Invasive Skin Tightening)A non-invasive energy-based modality that passes alternating electric current through skin so the tissue's own impedance generates heat (Joule heating), aiming to contract existing collagen and provoke a wound-healing collagen response. It has no chromophore target, so heating does not depend on skin colour.
Ingredients & Actives
- Azelaic acidAzelaic acid is a topical dicarboxylic acid used in specific medicinal formulations for acne and papulopustular rosacea, with narrower off-label evidence for melasma and post-inflammatory hyperpigmentation. Results depend on the finished product and indication; direct human pregnancy and breastfeeding outcome data are sparse.
- CeramidesCeramides are a diverse family of sphingolipids that, with cholesterol and free fatty acids, organise the stratum-corneum permeability barrier. In skincare, 'ceramide' names an ingredient, not a guaranteed finished-product effect: performance depends on species, companion lipids, concentration, vehicle and tested population.
- ExosomesExtracellular vesicles are lipid-bilayer particles released by cells that cannot replicate. “Exosome” names those of demonstrated endosomal origin, not a size class. In professional skincare, EV-containing preparations are applied topically after procedures that open the skin.
- Glycolic acidGlycolic acid is the smallest alpha-hydroxy acid, used at roughly 3–10% in cosmetic products and 20–70% as a professional peel agent. It does not self-neutralise: the reaction continues until an alkaline neutraliser stops it.
- Growth FactorsGrowth factors are signalling proteins that influence cell behaviour. In skincare they appear as recombinant proteins or complex conditioned-media preparations; topical studies report modest short-term appearance changes, but intact-skin delivery is unproven and human-derived cosmetic ingredients create a current Great Britain compliance concern.
- Hyaluronic AcidHyaluronic acid is a water-attracting glycosaminoglycan naturally present in skin and widely used in topical cosmetics, usually as sodium hyaluronate. Topical formulations can increase short-term surface hydration, but evidence does not show that they reach the dermis, repair the barrier or reproduce injectable effects.
- Lactic acidLactic acid is an alpha-hydroxy acid used at 5–12% in cosmetic products and from 10% to 92% as a professional peel. Lactate is also a genuine component of natural moisturising factor — which is a separate fact from what a free-acid peel does.
- NiacinamideNiacinamide, also called nicotinamide, is a form of vitamin B3 used topically for barrier, pigmentation, sebum and skin-ageing aims. Evidence exists across these areas, but effects are formulation- and outcome-specific; the breadth of research does not establish one universal concentration.
- PeptidesTopical cosmetic peptides are short amino-acid chains used in skincare as signal, carrier, neurotransmitter-inhibiting or enzyme-inhibiting ingredients. They are generally well tolerated, but clinical efficacy is formulation-specific, modest and largely manufacturer-supported; topical evidence is not comparable with prescription retinoids or injectable botulinum toxin.
- RetinoidsRetinoids are vitamin A-related compounds used topically in cosmetics and medicines. Prescription retinoids have established roles in acne and photoageing; cosmetic retinol, retinaldehyde and retinyl esters require conversion or formulation-dependent delivery and do not inherit that evidence automatically.
- Salicylic acidSalicylic acid is lipid-soluble 2-hydroxybenzoic acid, marketed as a BHA but structurally a phenolic aromatic acid. Used at 0.5–2% in cosmetics and 20–30% as a professional peel, it is desmolytic rather than keratolytic and is removed at a timed endpoint rather than neutralised.
- Sunscreen and SPFSunscreen is a finished topical formulation that reduces ultraviolet exposure at the skin. SPF is the ratio of erythema-producing UV doses on protected and unprotected skin under a standard test; it does not state hours of safe exposure, or by itself quantify UVA protection.
- Tranexamic acidTranexamic acid is an antifibrinolytic medicine also used for melasma by oral, topical and intradermal routes. Oral use for melasma is off-label and prescriber-led. Topical formulations beat vehicle and match hydroquinone in trials, but recurrence after stopping is common by any route.
- Vitamin C (ascorbic acid)Topical vitamin C includes L-ascorbic acid and several distinct derivatives used for antioxidant, pigmentation and photoageing aims. L-ascorbic acid is biologically established but difficult to formulate; clinical outcomes depend on the exact molecule, vehicle, stability and finished-product evidence.
Skin Science
- CollagenCollagen is the dominant structural protein of the dermis, providing tensile strength. Types I, III and V predominate in skin, and it turns over extremely slowly — a half-life estimated in years, not weeks. Most figures quoted about its loss and replacement do not survive checking.
- ContraindicationA documented reason not to give a treatment to a particular person. Absolute means do not treat at all; relative — properly a precaution — means weigh, modify or defer. In UK aesthetic practice the label is applied loosely, and the sources that generate it routinely disagree.
- FibroblastThe fibroblast is the principal synthetic cell of the dermis. It produces collagen, elastin and the extracellular matrix — and also the matrix metalloproteinases that degrade them. Stimulating it is the stated mechanism behind most regenerative skin treatments.
- Fitzpatrick scaleThe Fitzpatrick scale classifies six skin phototypes by their tendency to burn and tan after ultraviolet exposure. It was not designed to classify ethnicity or visible skin colour, and practitioners should not use it alone to predict treatment risk.
- MelanogenesisMelanogenesis is the production of melanin within melanocyte melanosomes and its subsequent distribution to keratinocytes. It is regulated by genetic, ultraviolet, visible-light, hormonal and inflammatory signalling; excessive or persistent activation contributes to hyperpigmentation disorders.
- Patch TestTwo different procedures sharing a name: diagnostic patch testing, a dermatology investigation applying standardised allergen concentrations under occlusion and reading them at fixed intervals to identify type IV delayed hypersensitivity; and the salon pre-service skin test, an unoccluded application of a working product read once by a lay person.
- Skin barrierSkin barrier describes the skin's coordinated ability to limit water and solute loss while resisting entry of irritants, allergens and microbes. The stratum corneum supplies most permeability resistance, but viable epidermal junctions, surface chemistry and immune defences also contribute. It is a function, not a film.
- Stratum corneumThe stratum corneum is the outermost epidermal layer: flattened, anucleate corneocytes joined by corneodesmosomes and embedded in organised extracellular lipids. Its thickness and composition vary by body site. It is the principal physical substrate of permeability-barrier function, but it is anatomy, not every barrier process.
- Transepidermal water loss (TEWL)Transepidermal water loss is the rate of water vapour passing outward through a defined area of skin. It is a research measure of the stratum corneum's water-permeability barrier — not a measure of hydration, not a diagnosis, and not a universal 'damaged barrier' score.
- Wound-healing cascadeThe wound-healing cascade is the overlapping sequence — haemostasis, inflammation, proliferation and remodelling — by which skin repairs injury. Controlled activation of it underpins microneedling, resurfacing and peels. The phases overlap rather than following one another in blocks.
Brands
- AnteAGEAnteAGE is a US professional skincare brand from Cellese Regenerative Therapeutics (Irvine, California), built on cell-free conditioned medium harvested from cultured human bone-marrow mesenchymal stem cells, supplemented with recombinant growth factors and cytokines, and — in some product lines — human bone-marrow- and umbilical-cord-derived exosomes.
- Circadia by Dr. PuglieseCircadia by Dr. Pugliese Inc. is a US professional skincare brand founded by physician Peter T. Pugliese and organised around a chronobiology theme: environmental defence by day, repair support at night. Its UK site names Unique Skin Ltd as operator but does not publish the registered contracting distributor.
- CosmacureCosmacure is a UK business-to-business professional skincare brand — the trading name of Medical Skincare Developments (UK) Limited, incorporated January 2026 — selling two bio-cellulose post-treatment sheet masks, XT73 Clinical Restorative and HPT78 Clinical Firming, to approved aesthetic clinic partners only.
- DermaceuticDermaceutic is a French professional skincare and chemical-peel brand operated by Lumiderme SASU. Its professional-only peels are marketed as Class IIa medical devices rather than cosmetics and reach the UK through third-party distributors. The range includes multi-acid, TCA and phenol-containing systems.
- DermalogicaA professional skincare brand founded in Los Angeles in 1986 by Jane and Raymond Wurwand and owned by Unilever's Prestige division since 2015. It sells a salon-channel professional range and a consumer retail range, and runs its own postgraduate training arm, the International Dermal Institute.
- Medik8A British cosmetic skincare brand (Medik8 Limited, company 03783618), founded 2009 by Elliot Isaacs, sold through both clinics and open retail. Known for retinaldehyde serums and the trademarked CSA Philosophy: vitamin C plus sunscreen by day, vitamin A by night.
- MesoesteticMesoestetic 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.
- skinbetter scienceA US professional-channel cosmetic skincare brand founded in 2016 and owned by L'Oreal since its 2022 acquisition agreement, sold in the UK through authorised clinics. Its signature ingredient is ethyl lactyl retinoate, an ester joining a retinoid to lactic acid, marketed as AlphaRet.
- SkinCeuticalsSkinCeuticals is a US professional skincare brand founded in 1994 and acquired by L'Oréal in 2005. It grew from Sheldon Pinnell's Duke University research on low-pH L-ascorbic acid formulations. Its UK serums, peels and other products are cosmetics rather than medicines.
- SkinPenSkinPen is a branded powered microneedling system made by Bellus Medical LLC, trading as Crown Aesthetics. Its 2018 US De Novo created the Class II microneedling-device type; the manufacturer describes broader CE-marked UK and EU uses, but no public certificate confirming those claims was located.
- ZO Skin HealthZO Skin Health, Inc. is a US physician-dispensed skincare brand founded in 2007 by dermatologist Zein Obagi and majority-owned by Blackstone since 2020. It is a separate company from Obagi Medical. Its US range has included prescription-only hydroquinone and tretinoin products; its UK range is cosmetic.
Why we’re building this.
Our mission at MSTA is to raise the standard of professional skincare and aesthetic treatment delivered across this industry. Not just for the people who train with us — for everyone working in it, and for every client sitting in a treatment chair trusting that the person holding the device knows what they are doing.
Most skincare information online is written for consumers, by people who have never performed the treatment. Search anything technical — needle depths, peel neutralisation, erythema grading, the difference between a Jessner and a TCA — and you will find either nothing, or something written to sell you a product. That gap is not harmless. It is where poor practice comes from.
Skinipedia is our attempt to close it. It is built to be used at work: opened between clients, checked mid-consultation, read properly on the evening you decide you want to genuinely understand the treatment you have been performing for two years. Every entry is written by educators who deliver these treatments on real clients every week, clinically reviewed before publication, referenced where the science matters, and dated so you know how current it is.
When you understand a treatment at that level, everything downstream improves — the information you give your clients, the expectations you set, the contraindications you catch, and the results you are able to defend. That is the whole point of it.
It is free, it always will be, and it is deliberately useful to people who will never train with us.