Emollients: Occlusives, Humectants, Creams, Ointments, Fire Safety & Clinical Use

Emollients: occlusives, humectants, creams, ointments, soap substitutes and safe clinical use

Emollients are topical preparations applied directly to the skin to soften, smooth, protect and hydrate it. They reduce water loss from the stratum corneum, fill microscopic cracks between corneocytes, reduce friction and help restore the barrier against irritants, allergens and microbes. The supplied 22-slide lesson describes the three central actions—occlusion, humectancy and lubrication—and the main forms: soap substitutes, bath oils, lotions, creams, ointments and sprays. This expanded note keeps all of those points and adds formulation science, application technique, quantities, interactions, adverse effects, fire prevention, emergency care and clinical cases.

Learning objectives

• Define emollients, moisturisers, occlusives, humectants and lubricants.
• Explain the epidermal barrier and how emollients reduce transepidermal water loss.
• Compare ointments, creams, lotions, gels, sprays, bath oils and soap substitutes.
• Select a formulation for dry, thick, hairy, weeping, infected, facial, flexural and palmoplantar skin.
• Teach correct quantity, frequency, direction of application, storage and hygiene.
• Use emollients safely with topical corticosteroids, keratolytics, antimicrobials, wet wraps and dressings.
• Recognise irritant dermatitis, allergic contact dermatitis, folliculitis, infection, slipping injuries and the serious fire hazard from emollient-coated fabrics.

1. Skin barrier physiology

The “brick-and-mortar” barrier

The outer epidermis is the stratum corneum. Flattened corneocytes act like bricks, while ceramides, cholesterol and fatty acids form the mortar. Natural moisturising factors inside the corneocytes bind water. When the barrier is damaged by eczema, psoriasis, frequent washing, solvents, cold weather, scratching, burns or irritants, water escapes through the skin and irritants enter more easily.

The result is a cycle: dryness causes itch, itch causes scratching, scratching creates more barrier breaks, and the damaged barrier permits more inflammation and microbial colonisation. An emollient breaks this cycle by placing water and lipids back into the outer layer and reducing friction while the underlying disease is treated.

Transepidermal water loss

Transepidermal water loss (TEWL) is the passive movement of water from deeper skin through the epidermis into the environment. TEWL rises when the stratum corneum is thin, inflamed, fissured or lipid-depleted. Occlusives reduce evaporation; humectants bind water; emollient lipids smooth the surface and fill gaps. Applying an emollient to slightly damp skin retains the water left after washing.

Emollient is not the same as every moisturiser

2. Classification of emollient ingredients

2.1 Occlusive ingredients

• Petrolatum/white soft paraffin: very effective, inexpensive and usually preservative-free; particularly useful for severe xerosis, fissures and night use.
• Liquid paraffin and mineral oil: spreadable oils that reduce water loss and add slip; often combined with white soft paraffin.
• Waxes: beeswax, paraffin wax and related materials add structure and a protective film.
• Silicones: dimethicone and related polymers form a breathable, water-resistant film and may be useful for irritant exposure.
• Plant oils and butters: can soften skin, but botanical ingredients may cause contact allergy in susceptible people and are not automatically safer than manufactured products.

2.2 Humectants

• Glycerol/glycerin: attracts water and is commonly used in creams and lotions.
• Urea: moisturises at low concentrations and becomes keratolytic at higher concentrations; see the separate keratolytic lesson for detailed concentration-dependent effects.
• Propylene glycol: humectant, solvent and penetration enhancer; can irritate or cause allergic contact dermatitis.
• Lactic acid and ammonium lactate: humectant alpha-hydroxy acids that can improve xerosis and ichthyosis but may sting fissured skin.
• Sodium PCA, sorbitol and hyaluronic acid: water-binding ingredients used in many modern formulations.

2.3 Physiologic lipids and emollient agents

Ceramides, cholesterol and free fatty acids resemble the lipid components of the barrier. Fatty alcohols, esters and triglycerides smooth the surface and improve spreadability. Some products combine physiologic lipids with petrolatum or dimethicone to address both the damaged mortar and evaporation.

3. Choosing the formulation

4. How emollients work

Occlusion

Petrolatum and paraffin create a continuous hydrophobic film over the stratum corneum. This decreases evaporation, increases hydration and makes dry corneocytes more flexible. Occlusion also increases penetration of some topical medicines, which is useful under deliberate short-term wet wraps but dangerous when it happens unintentionally over large areas.

Humectancy

Humectants bind water. They are most useful when the skin has access to water, such as after bathing, and when the formulation also contains an occlusive component to prevent the attracted water from evaporating. Humectants alone can feel sticky and may sting on fissured eczema.

Lubrication and friction reduction

Emollients reduce the friction of clothing, movement and scratching. This matters in flexures, hands, feet and babies, where repeated rubbing perpetuates inflammation. Smoothing rather than vigorous rubbing prevents heat and mechanical irritation.

Barrier and microbial effects

Restoring the barrier reduces penetration of soaps, detergents, allergens and irritants. It can also reduce fissures through which bacteria enter. Emollients do not sterilise the skin and do not replace antibiotics or antifungals when infection is diagnosed.

5. Indications

Atopic eczema

Use leave-on emollients generously on all dry skin, including skin that looks clear, because barrier weakness continues between flares. Continue maintenance after inflammation improves. Emollients reduce dryness, itch and cracking and may reduce the amount of topical corticosteroid needed, but an active flare may still require an anti-inflammatory treatment.

Psoriasis

Emollients soften scale, reduce fissuring and improve comfort. Thick plaques may also need a keratolytic such as urea or salicylic acid and a prescribed anti-inflammatory. Do not assume that every scaly plaque is psoriasis; tinea, seborrhoeic dermatitis, pityriasis rubra pilaris and cutaneous malignancy can mimic it.

Ichthyosis and severe xerosis

Use frequent moisturising, often with urea, glycerol, lactic acid or propylene glycol in addition to an occlusive base. High-strength keratolytic-humectants may be appropriate for thick localised scale but can sting fissured skin.

Irritant and allergic contact dermatitis

Remove the irritant or allergen, wash with a gentle substitute and apply a bland fragrance-free emollient. Occupational hand dermatitis often requires application after every hand wash and before exposure to water, detergents or gloves.

Hand and foot fissures

Thick ointment at night with cotton gloves or socks can reduce water loss. Inspect for tinea pedis, bacterial infection, neuropathy and vascular disease before using an occlusive regimen on the feet.

Dryness around wounds or dressings

Apply only to intact surrounding skin unless the product is specifically licensed for a moist wound environment. Avoid contaminating a tub by dipping fingers into it. Use a pump, single-use sachet or clean spatula for patients with infected or open skin.

6. Application technique

1. Choose a product the patient accepts: assess dryness, site, hair, weeping, climate, occupation, age and preference.
2. Use enough: under-application is one of the commonest reasons for failure. Extensive adult eczema may require several hundred grams weekly; quantity should be guided by the affected area and the product plan, not by a tiny cosmetic amount.
3. Apply after washing: pat dry gently and apply while the skin remains slightly damp, ideally within a few minutes.
4. Smooth, do not rub vigorously: spread in the direction of hair growth. Vigorous back-and-forth rubbing generates heat, increases itch and can block follicles.
5. Repeat regularly: at least twice daily for many patients and three or four times daily when dryness is severe, plus after hand washing, bathing or swimming. Follow the prescriber’s plan and the product label.
6. Continue during remission: maintenance emollient use is preventive, not only a response to visible eczema.
7. Keep containers clean: wash hands, use a pump or spatula, avoid sharing and discard contaminated product.
8. Prevent falls: use a non-slip bath mat, warn the patient and caregiver, and clean the bath or shower after using oil or greasy preparations.

How to smooth on an emollient

Place a small amount in the palm, warm it between the hands and gently smooth it over the skin following hair growth. Do not massage aggressively until the skin feels hot. For infants, caregivers should be shown the technique directly. For painful infected skin, use a spray or dab rather than rubbing.

Soap substitutes

Ordinary soaps, detergents, bubble baths and many shower gels strip surface lipids and may worsen eczema. A soap substitute can be applied before entering the shower or used as a wash in the water, then rinsed gently. It may not foam; lack of foam does not mean it has failed to clean. Avoid getting leave-on ointments in the eyes.

Bath oils and additives

Use only the labelled amount. Too much oil can irritate, leave an unsafe film and cause falls. Never leave a baby or frail patient unattended in an emollient bath. A leave-on emollient after bathing remains essential; bath additives should not replace it.

7. Emollients with other medicines

Topical corticosteroids

Emollients and corticosteroids are often used together in eczema and psoriasis. Apply the emollient generously to dry skin and the steroid only to active inflammatory areas. Many clinical services advise leaving approximately 20–30 minutes between products to minimise dilution and spread of steroid to unaffected skin; follow the local guideline and product instructions. Do not use emollient occlusion to justify prolonged high-potency steroid treatment on the face, groin, flexures or large areas.

Keratolytics

Urea and salicylic acid may be included in a medicated emollient or applied separately to thick scale. They can increase penetration of another topical medicine and may sting open skin. Start with a small area, avoid stacking several acids and reassess the need for a potent steroid.

Antifungals and antimicrobials

An emollient protects the barrier but does not kill dermatophytes, Candida, bacteria or viruses. If tinea, impetigo, infected eczema or scabies is diagnosed, use the specific antimicrobial treatment. Avoid heavily occluding an actively infected area unless a clinician deliberately chooses a dressing plan.

Wet wraps and dressings

Wet wraps can enhance hydration and reduce scratching in selected eczema flares, but they increase penetration of topical medicines and can cause chilling, maceration, folliculitis or infection. Use only with clear instructions about product, duration, layers, temperature, monitoring and when to stop.

8. Adverse effects and contraindications

Emollients are generally contraindicated only in known hypersensitivity to an ingredient, but a specific formulation may be unsuitable for a particular site. Avoid perfumed products on sensitive skin, heavy ointments on weeping eczema and unmonitored occlusion on infected or poorly perfused skin.

9. Fire safety: a non-negotiable counselling point

• Do not smoke, vape near a naked flame, cook over gas, use candles, use a heater or go near sparks while emollient-treated skin or fabric is present.
• Tell household members and carers, not only the patient. Mark the fire risk on care plans where large quantities are used.
• Change clothing, dressings and bedding regularly. Wash contaminated fabrics with detergent at the highest safe temperature; washing reduces build-up but may not remove all residue.
• Use extra caution with oxygen therapy, because oxygen enrichment increases combustion risk. Keep oxygen equipment away from flames and heat.
• Store tubs away from heat and children. Do not leave greasy cloths near a cooker, heater or electrical appliance.
• If a clothing fire occurs, stop, drop and roll or use a fire blanket/extinguisher if safe; call emergency services and treat burns according to local protocol.

10. Special populations and sites

Infants and children

Children have a relatively large surface-area-to-weight ratio and may ingest or spread products into the eyes. Use bland, fragrance-free preparations, supervise application, avoid slippery bath situations and keep all containers out of reach. Emollients may be used frequently and generously, but medicated emollients containing acids, steroids or antiseptics require a specific plan.

Older adults

Age-related dryness, reduced mobility, incontinence, neuropathy and falls increase risk. Choose a product that can be applied safely, inspect pressure areas and teach carers how to prevent bath and fire injuries.

Face, eyelids and flexures

Use lighter, non-comedogenic products and avoid eye contact. Thick occlusives may aggravate acne, perioral dermatitis, folliculitis or miliaria. In flexures, avoid prolonged maceration and inspect for candidiasis.

Hands

Apply after every wash when possible, before detergents or wet work, and at bedtime. Cotton gloves can improve overnight contact but should be clean and not used to occlude an active infection without guidance.

Feet

Inspect sensation, pulses, fissures and fungal infection. Avoid applying thick occlusive products between toes where moisture encourages maceration. Diabetes, neuropathy or vascular disease should prompt foot-care advice before acids or strong occlusion are used.

Pregnancy and breastfeeding

Plain petrolatum, glycerol and many bland emollients have minimal systemic absorption and are commonly used, but check each medicated ingredient. Avoid applying products to the nipple immediately before a feed unless the product is known to be safe and has been removed according to advice.

11. Emergency medicine considerations

Emollient-related burns

Assess airway, breathing and circulation, remove smouldering clothing, stop the burning process and cool thermal burns with cool running water according to local burn guidance. Do not apply more greasy product to a fresh burn. Estimate total body surface area, assess depth and refer burns involving the face, hands, feet, genitalia, major joints, circumferential areas or inhalation injury.

Eye exposure

Irrigate with clean water or saline, remove contact lenses and continue irrigation for at least 15 minutes if an irritant or medicated product enters the eye. Persistent pain, photophobia, reduced vision or chemical exposure warrants urgent ophthalmic assessment.

Accidental ingestion

Most bland emollients cause gastrointestinal upset rather than severe poisoning, but oil-based products can cause aspiration if vomited. Do not induce vomiting. Identify the exact product, assess the amount, airway and respiratory symptoms, and contact a poison centre. Medicated emollients may contain salicylate, steroids, antiseptics or other actives that change the risk.

Severe allergic reaction

Facial swelling, wheeze, hypotension or widespread urticaria after an emollient suggests anaphylaxis. Stop exposure and treat immediately according to local anaphylaxis protocol. A localised delayed rash is more consistent with contact dermatitis and still requires product withdrawal.

Infected eczema behind the “moisturiser” label

Fever, rapidly spreading erythema, pus, honey-coloured crusts, painful vesicles, punched-out erosions, lymphangitis or systemic illness require assessment for bacterial infection, eczema herpeticum or another emergency. Do not simply increase emollient frequency and delay antimicrobial or antiviral treatment.

12. Practical prescribing and patient education

13. Clinical cases

14. High-yield examination points

• Emollients have three classic actions: occlusion, humectancy and lubrication.
• Ointments are greasier and more occlusive; creams are easier to accept in the daytime; lotions spread over hairy or weeping skin but moisturise less.
• Apply generously and repeatedly, especially after bathing or hand washing, and continue even when eczema looks clear.
• Smooth in the direction of hair growth rather than rubbing vigorously.
• Use bland soap substitutes instead of ordinary soap when detergents worsen the barrier.
• Urea, glycerol and lactic acid may sting fissured or inflamed skin; petrolatum may be better tolerated during a painful flare.
• Heavy occlusion can cause folliculitis, acne, maceration and increased absorption of topical steroids or keratolytics.
• Emollients do not treat infection; fever, pus, rapidly spreading redness or punched-out erosions require urgent assessment.
• All paraffin-containing emollients can make fabrics ignite more readily, and the risk cannot be excluded with paraffin-free products.
• Bath oils make surfaces slippery. Always use fall-prevention measures.

15. Sources and further study

• Supplied SlideShare: Emollients
• NHS: Emollients—forms, application, washing and fire safety
• DermNet: Emollients and moisturisers
• DermNet CME: Emollients in dermatitis
• NICE: Atopic eczema—emollient education and application
• MHRA/GOV.UK: Fire risk with paraffin-containing and paraffin-free emollients
• GOV.UK: Paraffin-based emollients on dressings and clothing
• DermNet: Barrier creams, occlusives and humectants