Lesson 1Preservatives, fragrances, and potential irritants: parabens, isothiazolinones, fragrance allergens — relevance for sensitive skinThis analysis covers preservatives, fragrances, and other potential irritants. It includes parabens, isothiazolinones, formaldehyde releasers, and fragrance allergens, stressing patch testing, regulatory thresholds, and advice for sensitive or atopic skin.
Common preservative classes and safety dataIsothiazolinones and formaldehyde releasersFragrance allergens and labelling rulesFormulating for sensitive and atopic skinPatch testing and counselling on avoidanceLesson 2Retinoids and retinoid alternatives: tretinoin, adapalene, retinol, retinaldehyde — mechanism, efficacy, irritation managementThis exploration covers topical retinoids and alternatives, including tretinoin, adapalene, retinol, and retinaldehyde. It discusses receptor interactions, evidence for acne and photoageing, gradual introduction methods, buffering techniques, and handling irritation and initial purging.
Retinoid classes and receptor selectivityAcne vs photoageing: evidence and regimensRetinol and retinaldehyde: conversion stepsInitiation, titration, and buffering methodsManaging irritation, purging, and adherenceLesson 3Excipients and vehicles affecting delivery: pH, liposomes, esters, gels, creams, oil-in-water vs water-in-oil impact on actives and tolerabilityThis examination reviews how excipients and vehicles influence delivery, efficacy, and tolerability. It compares gels, creams, lotions, and ointments, pH influences, liposomes and esters, and the effects of oil-in-water versus water-in-oil systems on penetration.
pH impact on ionisation and irritationOil-in-water vs water-in-oil: key differencesLiposomes and encapsulation for activesRole of esters and solvents in penetrationSelecting vehicles for skin type and diseaseLesson 4Lightening pathway modulators: hydroquinone, azelaic acid, tranexamic acid — mechanisms and cautionsThis coverage includes hydroquinone, azelaic acid, and tranexamic acid as modulators of melanogenesis and vascular elements. It details mechanisms, dosing, treatment durations, rebound risks, and safety considerations across different skin phototypes.
Hydroquinone: mechanism and cycling regimensAzelaic acid for pigment and acne overlapTranexamic acid: topical and oral usePost-inflammatory hyperpigmentation strategiesSafety in darker phototypes and pregnancyLesson 5Photoprotection actives and filters: UVA/UVB chemical filters, mineral filters (zinc oxide, titanium dioxide), photostability, broad-spectrum requirementsThis review encompasses organic and mineral UV filters, including zinc oxide and titanium dioxide. It explains UVA and UVB protection, SPF and PPD principles, photostability, filter synergies, and regulatory and labelling aspects of broad-spectrum assertions.
UVA vs UVB: clinical and labelling relevanceOrganic filters: profiles and combinationsMineral filters: particle size and aestheticsPhotostability and use of stabilising systemsBroad-spectrum, SPF, and PPD requirementsLesson 6Sunscreen adjuncts and enhancers: photostabilisers, antioxidants, intended claimsThis focus is on sunscreen adjuncts that augment protection, such as photostabilisers and antioxidants. It explores mechanisms, evidence for mitigating photoageing, marketing assertions, and how adjuncts affect texture and user compliance.
Photostabilisers for vulnerable UV filtersAntioxidants in sunscreens: added benefitsBlue light and infrared protection claimsImpact on cosmetic elegance and adherenceEvaluating evidence behind marketing claimsLesson 7Anti-inflammatory and barrier-supporting actives: ceramides, fatty acids, cholesterol, panthenol, colloidal oatmeal, allantoinThis detail covers barrier-supporting and soothing actives like ceramides, fatty acids, cholesterol, panthenol, colloidal oatmeal, and allantoin. It explains barrier repair ratios, anti-inflammatory effects, and applications in dermatitis and post-procedure care.
Ceramide, cholesterol, fatty acid ratiosPanthenol and allantoin: soothing mechanismsColloidal oatmeal: anti-itch and barrier effectsBarrier repair in eczema and irritant dermatitisPost-procedure recovery and product layeringLesson 8Antioxidants and brightening agents: vitamin C (ascorbic acid forms), niacinamide, alpha arbutin, kojic acid — stability, interactions, clinical indicationsThis detail includes vitamin C variants, niacinamide, alpha arbutin, and kojic acid. It discusses antioxidant and brightening mechanisms, stability issues, suitable pH ranges, compatibility with other actives, and evidence-based uses for pigmentation disorders.
Ascorbic acid vs derivatives and pH needsNiacinamide: barrier, tone, and tolerabilityAlpha arbutin and kojic acid: pigment targetsFormulation and packaging for antioxidant stabilityCombining brighteners with retinoids and acidsLesson 9Keratolytics and comedolytics: salicylic acid, benzoyl peroxide, azelaic acid — concentrations, vehicles, side effectsThis review addresses keratolytics and comedolytics such as salicylic acid, benzoyl peroxide, and azelaic acid. It covers mechanisms, optimal concentrations, vehicle choices, bleaching risks, irritation, and integration with retinoids or antibiotics.
Salicylic acid: pH, strength, and vehiclesBenzoyl peroxide: efficacy and bleaching riskAzelaic acid: dual comedolytic and brighteningCombining with retinoids and topical antibioticsIrritation, dryness, and mitigation tacticsLesson 10Humectants and emollients: glycerin, hyaluronic acid, urea — function and formulation considerationsThis exploration includes humectants and emollients like glycerin, hyaluronic acid, and urea. It covers water-binding mechanisms, barrier support, ideal concentrations, synergy with occlusives, and formulation options for dry, sensitive, and ageing skin.
Glycerin: mechanism, levels, and skin feelHyaluronic acid weights and crosslinkingUrea concentrations and indicationsCombining humectants, emollients, occlusivesFormulation tips for dry and sensitive skin
