yeast (including those containing ketoconazole p. 725 and
coal tar) and combinations of mild topical corticosteroids
with suitable antimicrobials are used to treat older children.
Medicated bandages
Zinc paste bandages (seeWound management products and
elasticated garments) are used withcoal taror ichthammol in
chronic lichenified skin conditions such as chronic eczema
(ichthammol often being preferred since its action is
considered to be milder). They are also used with calamine in
milder eczematous skin conditions.
Psoriasis
Management
Psoriasis is characterised by epidermal thickening and
scaling. It commonly affects extensor surfaces and the scalp.
For mild psoriasis, reassurance and treatment with an
emollient may be all that is necessary.Guttate psoriasisis a
distinctive form of psoriasis that characteristically occurs in
children and young adults, often following a streptococcal
throat infection or tonsillitis.
Occasionally psoriasis is provoked or exacerbated by drugs
such as lithium, chloroquine and hydroxychloroquine, beta-
blockers, non-steroidal anti-inflammatory drugs, and ACE
inhibitors. Psoriasis may not occur until the drug has been
taken for weeks or months.
Emollients, in addition to their effects on dryness, scaling
and cracking, may have an antiproliferative effect in
psoriasis. They are particularly useful ininflammatory
psoriasisand inchronic stable plaque psoriasis.
Forchronic stable plaque psoriasison extensor surfaces of
trunk and limbs preparations containingcoal tarare
moderately effective, but the smell is unacceptable to some
children.Vitamin Dand its analogues are effective and
cosmetically acceptable alternatives to preparations
containing coal tar or dithranol p. 745. Dithranol is an
effective topical antipsoriatic agent but it irritates and stains
the skin and it should be used only under specialist
supervision. Adverse effects of dithranol are minimised by
using a‘short-contact technique’and by starting with low
concentration preparations. Tazarotene, a topical retinoid
for the treatment of mild to moderate plaque psoriasis, is not
recommended for use in children under 18 years. These
medications can irritate the skin particularly in theflexures
and they are not suitable for the more inflammatory forms of
psoriasis; their use should be suspended during an
inflammatory phase of psoriasis. The efficacy and the
irritancy of each substance varies between patients. If a
substance irritates significantly, it should be stopped or the
concentration reduced; if it is tolerated, its effects should be
assessed after 4 to 6 weeks and treatment continued if it is
effective.
Widespreadunstable psoriasisof erythrodermic or
generalised pustular type requires urgent specialist
assessment. Initial topical treatment should be limited to
using emollients frequently and generously. More localised
acute or subacuteinflammatory psoriasiswith hot, spreading
or itchy lesions, should be treated topically with emollients
or with a corticosteroid of moderate potency.
Scalp psoriasisis usually scaly, and the scale may be thick
and adherent. This requires softening with an emollient
ointment, cream, or oil and usually combined with salicylic
acid p. 768 as a keratolytic.
Some preparations for psoriasis affecting the scalp
combine salicylic acid with coal tar orsulfur. The
preparation should be applied generously and left on for at
least an hour, often more conveniently overnight, before
washing it off. If a corticosteroid lotion or gel is required (e.g.
for itch), it can be used in the morning.
Flexural psoriasiscan be managed with short-term use of a
mild potency topical corticosteroid. Calcitriol p. 631 or
tacalcitol p. 751 can be used in the longer term; calcipotriol
p.^750 is more likely to cause irritation inflexures and should
be avoided. Low-strength tar preparations can also be used.
Facial psoriasiscan be treated with short-term use of a
mild topical corticosteroid; if this is ineffective, calcitriol,
tacalcitol, or a low-strength tar preparation can be used.
Calcipotriol and tacalcitol are analogues of vitamin D that
affect cell division and differentiation. Calcitriol is an active
form of vitamin D. Vitamin D and its analogues are used as
first-line treatment for plaque psoriasis; they do not smell or
stain and they may be more acceptable than tar or dithranol
products. Of the vitamin D analogues, tacalcitol and
calcitriol are less likely to irritate.
Coal tar p. 745 has anti-inflammatory properties that are
useful in chronic plaque psoriasis; it also has antiscaling
properties. Contact of coal tar products with normal skin is
not normally harmful and preparations containing coal tar
can be used for widespread small lesions; however, irritation,
contact allergy, and sterile folliculitis can occur. Leave-on
preparations that remain in contact with the skin, such as
creams or ointments, containing up to 6 % coal tar may be
used on children 1 month to 2 years; leave-on preparations
containing coal tar 10 % may be used on children over 2 years
with more severe psoriasis. Tar baths and tar shampoos may
also be helpful.
Dithranol is effective for chronic plaque psoriasis. Its
major disadvantages are irritation (for which individual
susceptibility varies) and staining of skin and of clothing.
Dithranol is not generally suitable for widespread small
lesions nor should it be used in theflexures or on the face.
Proprietary preparations are more suitable for home use;
they are usually washed off after 20 – 30 minutes (‘short
contact’technique). Specialist nurses may apply intensive
treatment with dithranol paste which is covered by
stockinette dressings and usually retained overnight.
Dithranol should be discontinued if even a low
concentration causes acute inflammation; continued use can
result in the psoriasis becoming unstable.
A topicalcorticosteroidis not generally suitable for long-
term use or as the sole treatment of extensive chronic plaque
psoriasis; any early improvement is not usually maintained
and there is a risk of the condition deteriorating or of
precipitating an unstable form of psoriasis e.g.
erythrodermic psoriasis or generalised pustular psoriasis on
withdrawal. Topical use of potent corticosteroids on
widespread psoriasis can also lead to systemic as well as local
side-effects. However, topical corticosteroids used short-
term may be appropriate to treat psoriasis in specific sites
such as the face orflexures with a mild corticosteroid, and
psoriasis of the scalp, palms, and soles with a potent
corticosteroid. Very potent topical corticosteroids should
only be used under specialist supervision.
Combining the use of a corticosteroid with another specific
topical treatment may be beneficial in chronic plaque
psoriasis; the drugs may be used separately at different times
of the day or used together in a single formulation.Eczema
co-existing with psoriasis may be treated with a
corticosteroid, or coal tar, or both.Phototherapy
Phototherapyis available in specialist centres under the
supervision of a dermatologist. Narrow band ultraviolet B
(UVB) radiation is usually effective forchronic stable psoriasis
and forguttate psoriasis. It can be considered for children
with moderately severe psoriasis in whom topical treatment
has failed, but it may irritate inflammatory psoriasis. The use
of phototherapy and photochemotherapy in children is
limited by concerns over carcinogenicity and premature
ageing.BNFC 2018 – 2019 Eczema and psoriasis 731
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