Lesson 1Antimicrobials and microbiome-friendly actives: benzoyl peroxide, azelaic acid, topical antimicrobials and resistance considerationsThis section discusses topical antimicrobials and microbiome-aware actives, including benzoyl peroxide and azelaic acid. It covers mechanisms, resistance issues, microbiome changes, and ways to limit imbalance while treating conditions.
Benzoyl peroxide: bactericidal action and irritationAzelaic acid: antimicrobial and anti-inflammatoryTopical antibiotics and resistance mitigationMicrobiome shifts in acne and dermatitisNon-antibiotic antimicrobial strategiesCombining antimicrobials with barrier supportLesson 2Surfactants and cleansers: non-foaming vs foaming, pH and barrier impactThis section analyses surfactant chemistry and cleanser design, comparing foaming and non-foaming types. It addresses pH, lipid removal, barrier effects, and selecting cleansers for acne, rosacea, atopic skin, and post-procedure care.
Anionic, amphoteric, and nonionic surfactant classesFoaming vs non-foaming systems and skin feelCleanser pH, acid mantle, and TEWL changesSyndets vs true soaps in dermocosmeticsCleanser selection for acne and oily skinCleansers for atopic, rosacea, and aged skinLesson 3Sunscreen filters: chemical vs mineral filters, UVA/UVB coverage, photostability, and vehicle effectsThis section looks at organic and mineral sunscreen filters, UVA and UVB protection, and photostability. It discusses vehicles, film formation, cosmetic appeal, and filter interactions with other actives in routines.
UVA vs UVB: action spectra and skin outcomesOrganic filters: mechanisms and safety profileMineral filters: particle size and whiteningPhotostability, filter pairing, and boostersVehicle types, film formation, and adherenceCombining sunscreens with irritant-prone activesLesson 4Anti-inflammatory and barrier-repair agents: niacinamide, panthenol, ceramides, cholesterol, fatty acidsThis section explores anti-inflammatory and barrier-repair ingredients like niacinamide, panthenol, ceramides, cholesterol, and fatty acids. It links molecular effects to outcomes in acne, rosacea, atopic dermatitis, and irritant dermatitis.
Niacinamide: mechanisms, benefits, and limitsPanthenol and soothing of acute irritationCeramide subclasses and lamellar organisationCholesterol and fatty acids in barrier balanceOptimal ceramide:cholesterol:fatty acid ratiosBarrier repair in atopic and irritant dermatitisLesson 5Preservatives, fragrance, and common sensitisers: parabens, formaldehyde releasers, essential oilsThis section reviews preservatives, fragrance elements, and typical sensitisers. It explains preservation mechanisms, allergenic pathways, patch test importance, and choosing lower-risk options for sensitive or compromised skin.
Mechanisms of cosmetic preservation and stabilityParabens: safety data, myths, and regulatory statusFormaldehyde releasers and contact allergy riskFragrance mixes, essential oils, and sensitisationLabel reading for fragrance-free and hypoallergenicPatch testing relevance and counselling patientsLesson 6Antioxidants and supportive actives: vitamin C (ascorbic acid), tocopherol, and niacinamide interactionsThis section reviews main antioxidant and supportive actives, focusing on vitamin C, vitamin E, and niacinamide. It covers stability, synergistic mixes, potential clashes, and protection against oxidative stress.
Oxidative stress pathways in skin ageingAscorbic acid forms, pH, and stabilisationTocopherol and lipid phase antioxidant synergyVitamin C and E co-formulation strategiesNiacinamide interactions with acidic formulasAntioxidants in photoprotection regimensLesson 7Retinoids and retinaldehyde: efficacy, irritation management, and photosensitivityThis section details topical retinoids, including retinol, retinaldehyde, and prescription versions. It reviews mechanisms, evidence for antiageing and acne, irritation causes, photosensitivity, and tolerance-building strategies.
Retinoid family overview and skin pharmacologyEvidence for acne, photoageing, and dyschromiaRetinaldehyde vs retinol: potency and tolerabilityIrritation mechanisms and barrier impairmentRetinisation protocols and buffering strategiesPhotosensitivity, photoprotection, and timingLesson 8Humectants and hydrators: hyaluronic acid, glycerin, propanediol — molecular weight considerationsThis section explores humectants and water-binding hydrators like hyaluronic acid, glycerin, and propanediol. It explains molecular weight, penetration, stickiness, and pairing with occlusives to avoid barrier dehydration.
Mechanisms of humectancy and water bindingHyaluronic acid molecular weights and effectsGlycerin: efficacy, safety, and sensory profilePropanediol and multifunctional solvent rolesPairing humectants with occlusives and emollientsHydrator choices for oily vs very dry skinLesson 9Keratolytics and exfoliants: salicylic acid, glycolic acid, lactic acid — concentration, pH, and irritation riskThis section analyses keratolytics and exfoliants such as salicylic, glycolic, and lactic acids. It covers concentration, pH, penetration depth, and irritation risk, guiding safe use in acne, photoageing, dyschromia, and sensitive skin.
Beta-hydroxy vs alpha-hydroxy acid mechanismsRole of pH and concentration in acid potencySalicylic acid in acne and seborrheic skinGlycolic acid for photoageing and dyschromiaLactic acid for dry and sensitive-prone skinLayering acids with retinoids and vitamin C
