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cholesterol-lowering agents (e.g. statins)
and anti-androgens (e.g. bicalutamide,
enzalutamide) can also cause or
exacerbate dry skin.
What are the clinical features of
Xerosis is commonly seen on the legs
(particularly the shins), but can also be
present on the hands, arms and trunk.
The skin is scaly, cracked and fissured
due to epidermal water loss. It may
be described as looking like crazy
paving or cracked porcelain (known as
eczema craquele or asteatotic eczema).
Asteatotic eczema is often accompanied
by intense itching, excoriations (due to
scratching) and inflammatory changes. If
fissuring is deep, there may be bleeding.
Environmental allergens and pathogens
can penetrate the skin through fissures,
increasing the risk of allergic and irritant
contact dermatitis and infection.
How can skin dryness be treated?
The aims of treating dry skin are to
restore the epidermal barrier of the
skin and to maintain hydration of the
moisturisers are first-line treatment
for dry skin. They help to rehydrate
the skin and maintain skin integrity.5
The terms ‘emollient’ (softens the skin)
and ‘moisturiser’ (increases the moisture
content of the skin) are often used
12 For the purposes of
this article, ‘moisturiser’ will be used as
an overarching term.
Moisturisers fall into two main
1. Occlusives – prevent evaporation of
water from the skin by forming an
oily film that impedes transepidermal
water loss (TEWL).
2. Humectants – draw water from
deeper skin layers up to the stratum
Petrolatum is the most effective
occlusive moisturiser, reducing TEWL
by 99%. Other occlusive moisturisers
include liquid paraffin, silicones
(e.g. dimethicone), cocoa butter and
lanolin. These reduce TEWL by 20–30%.
Occlusive moisturisers also diffuse
throughout the stratum corneum
intercellular spaces, promoting the
initiation of stratum corneum repair
Humectants, in addition to drawing
water from the dermis into the stratum
corneum, also promote absorption of
water from the external environment
into the skin when conditions are humid.
Many humectants also have emollient
properties. Glycerol and urea are two
of the most effective humectants.
Moisturisers containing only
humectants can increase TEWL when
applied to a damaged or dehydrated
stratum corneum, because they do
not prevent loss to the atmosphere of
the water drawn up from the dermis.
Therefore, an effective moisturiser
should contain a humectant and an
occlusive, to enhance both epidermal
hydration and barrier function.2,13
See Table 2 for examples of occlusives
When recommending a moisturiser,
consider the patient’s preferences, and
how dry their skin is. Patients are more
likely to use the moisturiser regularly
if they are using a preparation they
are comfortable with.
usually work by occlusion. They have
the highest oil content and are the
most effective moisturisers. However,
they are greasy and can be messy
to apply, leave the skin with a shiny
appearance, and can stain clothes. They
are suitable for very dry skin and may
be best applied at night. Creams work
by occlusion or humectant effects.
They are rapidly absorbed and more
cosmetically acceptable. They are less
effective moisturisers than ointments,
but may be good for daytime use.
Lotions contain less oil and more water.
They are the lightest and least greasy
moisturisers, and are not suitable for dry
Alpha-hydroxy acids, which may
be present in moisturisers for their
humectant properties, can cause
stinging and irritation. Therefore,
moisturisers containing these should
be avoided by people with sensitive
10 Urea should not be used on
broken, infected or severely inflamed
skin. Lanolin can cause allergic contact
dermatitis, with severe swelling and
redness developing hours to 1–2 days
after initial application. This is more
likely to occur in people who are atopic.6
Moisturisers should be applied to the
skin at least twice daily, soon after
bathing and at bedtime, and at other
times if necessary.
should be applied in a downward
COUNSELLING IN PRACTICE
Table 2. Common moisturising agents2,13,14
acids (e.g. glycolic
acid, lactic acid)
Table 3. Recommended quantities of moisturiser to be used for adults (twice daily application for
Both arms or legs
Groin and genitalia
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