Lesson 1Soothing and barrier-repair actives: panthenol, niacinamide, ceramides, cholesterol, fatty acids, oat extract (Avena), and use-level guidanceExplore calming and barrier-fixing actives ideal for sensitive, dehydrated skin. Understand their actions and recommended levels for panthenol, niacinamide, ceramides, cholesterol, fatty acids, and oat extracts in simple formulas.
Panthenol for soothing and barrier recoveryNiacinamide at low, tolerable inclusion levelsCeramide, cholesterol, fatty acid ratiosColloidal oatmeal and oat-derived activesCombining actives without overloading skinLesson 2Design principles for sensitive-dehydrated skin: minimalism, low-irritancy, barrier-supporting, humectant-emollient balanceOutline main design principles for sensitive, dehydrated skin: keeping it simple, low-irritant, and barrier-focused. Learn to restrict actives, cut redundancy, and balance humectants with emollients in a straightforward routine.
Minimalist INCI lists and formula focusAvoiding common irritant and sensitizer groupsHumectant–emollient–occlusive balancingLayering strategy across a simple routinePatch testing and gradual introductionLesson 3Humectants, occlusives, and emollients: glycerin, hyaluronic acid, propanediol, squalane, esters, and fatty alcohols with suggested use-level rangesSee how humectants, occlusives, and emollients team up to hydrate sensitive, dehydrated skin. Check out glycerin, hyaluronic acid, propanediol, squalane, esters, and fatty alcohols with handy use-level suggestions.
Water-binding humectants and optimal levelsHyaluronic acid types and molecular weightsLight emollients: squalane and estersFatty alcohols for structure and mildnessBalancing humectant load to avoid tightnessLesson 4pH targeting and buffer systems: safe pH ranges for skin, stability considerations, and ingredient compatibilityMaster aiming for skin-friendly pH levels and building buffer systems that safeguard both skin and formula. Tackle compatibility with actives, surfactants, and preservatives, plus watch for pH changes over time.
Physiological pH range and barrier impactpH needs of surfactants and preservativesSelecting acids, bases, and buffersManaging pH drift during stability testspH considerations for exfoliating activesLesson 5Preservative approaches suitable for sensitive skin: approved preservative families, typical levels, synergists, and preservative-free risk managementLook at preservative options right for sensitive formulas. Compare approved types, usual levels, and helpers, and get the lowdown on risks and controls for going preservative-free.
Regulatory status of key preservative groupsOrganic acids and mild preservative blendsChelators and humectants as boostersChallenge testing and PET requirementsRisk of under-preservation and recallsLesson 6Fragrance and allergen strategy: fragrance-free vs masked scents, IFRA considerations, and EU/allergen declarationCreate a fragrance and allergen plan for sensitive skin. Weigh up fragrance-free, essential oils, and low-allergen mixes, follow IFRA guidelines, and handle EU-style allergen labelling and customer hopes.
Fragrance-free versus low-scent approachesEssential oils and sensitization riskUsing IFRA categories and maximum levelsLabeling listed fragrance allergensMasking base odors without overloadingLesson 7Gentle surfactants and mild cleansing systems: non-ionic/amine oxide/zwitterionic options and concentration guidanceFind out how to pick super-mild surfactant setups for cleansers aimed at sensitive, dehydrated skin. Compare nonionic, amine oxide, and zwitterionic choices, set safe levels, and craft low-foam, gentle bases.
Irritation mechanisms of common surfactantsNonionic surfactants for sensitive skinAmine oxides and zwitterionic co-surfactantsDesigning low-foam, creamy cleanser basesActive surfactant level and dilution guidanceLesson 8Ingredient selection framework: prioritising safety, evidence, and multifunctional activesPut together an ingredient picking framework that puts safety, proof, and multi-tasking first. Learn to read safety info, balance in vivo and in vitro evidence, and choose ingredients that offer multiple perks.
Reading safety assessments and CIR opinionsEvaluating clinical and instrumental dataChoosing multifunctional emollient-humectantsSupplier documentation and quality checksDecision trees for go or no-go ingredientsLesson 9Formulation rheology and sensorial design: emulsion types (O/W, water-serum, gel-cream), viscosity modifiers, and sensory targets for a minimalist lineGet expert in rheology and sensorial design for simple systems. Compare O/W creams, water-serums, and gel-creams, pick viscosity adjusters, and fine-tune slip, playtime, and afterfeel for delicate, overload-prone skin.
Choosing emulsion type for skin conditionPolymeric versus natural thickenersSlip, playtime, and afterfeel optimizationLightweight gel-creams for dehydrationStability checks for low-oil systemsLesson 10Skin physiology and pathophysiology: barrier function, TEWL, sensitive skin triggers, and dehydration vs drynessDelve into how damaged barriers, TEWL, and overactive nerves characterise sensitive, dehydrated skin. Identify main triggers, the difference between dehydration and dryness, and implications for textures, actives, and surfactants.
Stratum corneum structure and lipid organizationTEWL, corneometry, and hydration assessmentNeurosensory hyperreactivity and stingingTriggers: surfactants, pH, fragrance, alcoholsDehydration versus true lipid dryness
