Emollients (Moisturizers)

Introduction

Emollients soothe, smooth and hydrate the skin and are indicated for all dry or scaling disorders. They are useful in dry and eczematous disorders, and to a lesser extent in psoriasis.

Emollients effects are short lived and they should be applied frequently even improvement occurs.

  • Can be used at any time but are most effective when they are applied to damp skin, e.g. immediately after bathing or washing your face or hands.



Dosage and Administration

Apply by smoothing it into the skin in the same direction the hair grows and do not rub in. Use frequently and liberally.



Forms and Review

Emollient comes in various forms, including ointments, lotions, cream, lotions and bath oils. The choice of an appropriate emollient depends on multiple factors, such as severity of the condition, patient preference and site of application.

  • Lotions – good for hairy or damaged areas of skin (such as weeping eczema) as they're thin and spread easily, but aren't very moisturizing.
  • Sprays – good for hard-to-reach areas and sore or infected skin that shouldn't be touched, and are absorbed quickly.
  • Creams – good for daytime use as they're not very greasy and are absorbed quickly.
  • Ointments – good for very dry, thickened skin and night-time use as they're greasy, thick and very moisturizing; they're usually free of preservatives so are suitable for sensitive skin, but shouldn't be used on weeping eczema.
  • Bath oils and shower products
  • Soap substitutes

In general, the heavier or greasier the preparation, the more effective the moisturizing qualities. Soft paraffin is the most occlusive, however it is not widely used on its own due to its greasy effect.

A 2017 systematic review of 77 studies including 6603 participants (mean age 19 years) with mostly mild to moderate eczema evaluated the efficacy of emollients and moisturizers in reducing the signs and symptoms of eczema and the frequency of flares:

  • Based on both physician and patient assessment, the use of any moisturizers reduced eczema severity and itch compared with no use, resulted in fewer flares, and reduced the need for topical corticosteroids.
  • In 3 studies, patients found that a moisturizer containing glycyrrhetinic acid (a natural anti-inflammatory agent) was four times more effective than vehicle in reducing eczema severity.
  • In 4 studies, patients using a cream containing urea (a humectant agent) reported improvement more often than those using a control cream without urea.
  • 3 studies assessed a moisturizer containing glycerol (a humectant agent) versus control. More patients in the glycerol group experienced skin improvement, both by physician and patient assessment.
  • 4 studies examined oat-containing moisturizers versus no treatment or control. No significant difference in skin improvement was noted between groups, although patients using oat moisturizers tended to have fewer flares and reduced need for topical corticosteroids.



Topical Application with Topical Corticosteroids

There are conflicting recommendations on the sequence of application. Personally, I recommend patients to apply emollient first, and only apply topical steroids after at least 30 minutes.



Aqueous Cream and Emulsifying Ointment

On March 2013, the Medicines and Healthcare products Regulatory Agency (MHRA) issued an official warning that aqueous cream may cause skin irritation, particularly in children with eczema, possibly due to sodium lauryl sulphate (SLS), which is a known skin irritant. Rather, preparations such as aqueous cream and emulsifying ointment can be used as soap substitutes for hand washing and in the bath; the preparation is rubbed on the skin before rinsing off completely.

According to British Pharmacopoeia, the formulation of aqueous cream:

  • Emulsifying ointment, 300 g
  • Phenoxyethanol, 10 g
  • Purified water, freshly boiled and cooled, sufficient to produce 1000 g.

The formulation of emulsifying ointment:

  • White soft paraffin, 500 g
  • Emulsifying wax, 300 g
  • Liquid paraffin, 200 g

However, there is 2 formulations of emulsifying wax

  • Anionic emulsifying wax
    • Cetosterayl alcohol, 90 g
    • Sodium lauryl sulphate, 10 g
    • Purified water, 4 ml
  • Cetomacrogol emulsifying wax
    • Cetostearyl alcohol, 800 g
    • Macrogol cetosterayl ether 200g

By understanding the formulation, one may argue that

  • Aqueous cream made from cetomacrogol emulsifying wax (SLS-free formulation) may not irritate the skin when it is left for a long time.
  • On the other hand, aqueous cream that contains sodium lauryl sulphate (using anionic emulsifying wax) should be rinsed off after use.



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