A Textbook of Clinical Pharmacology and Therapeutics

DERMATITIS (ECZEMA)

PRINCIPLES OF TREATMENT

The most common forms of dermatitis that present to physi-
cians are atopic dermatitis, synonymous with atopic eczema,
seborrhoeic dermatitis and contact dermatitis. An algorithm
for treatment of dermatitis is shown in Figure 51.2.
Management of atopic eczema should include avoidance of
trigger factors and the use of emollients. Dry skin is a major
factor and emollients should be used when bathing and
applied as often as necessary. A simple emollient (an aqueous
cream, e.g. E45 or Alpha Keri) is usually all that is necessary for
dry, fissured scaly lesions. Inflammation should be treated
with short courses of mild to moderate topical glucocortico-
steroids. A more potent glucocorticosteroid may be required for
particularly severely affected areas or for a more general flare
up. Oral antihistamines are often effective in reducing pruritus.
Ichthammolandzinc creammay be used in chronic licheni-
fied forms of eczema. Potassium permanganatesolution can
be used in exudating eczema for its antiseptic and astringent
effect; treatment should be stopped when weeping stops.

Weeping eczema may require topical glucocorticosteroids and

often antibiotics to treat secondary infection. Immunosuppres-

sant therapy, such as ciclosporin, is sometimes effective in

severe, resistant eczema. Ultraviolet B or psoralenultraviolet

A (PUVA), or an immunosuppressive agent (e.g. azathioprine,

ciclosporin or mycophenolate mofetil, Chapter 50) are

also used.

Seborrhoeic dermatitis may respond to a mild topical glu-

cocorticosteroid. Scalp seborrhoeic dermatitis is often improved

by coal tar, salicylic acid and sulphur preparations. (Fungal

infection should be ruled out if there is no response.)

Contact dermatitis is caused by external agents (e.g. nickel),

but often complicates a pre-existing dermatitis. Avoidance of

precipitating factors, emollients and topical glucocorticosteroids

are used.

GLUCOCORTICOSTEROIDS

Topical glucocorticosteroids act as anti-inflammatory vasocon-

strictors and reduce keratinocyte proliferation. They include

hydrocortisoneand its fluorinated semi-synthetic derivatives,

which have increased anti-inflammatory potency compared to

hydrocortisone (Chapter 40).

DERMATITIS(ECZEMA) 413

Avoid precipitating factors

Emollients

Dry, fissuring Weeping, exudating

Potassium permanganate solution

Antibiotics (if secondary infection)

Aqueous cream

Emulsifying ointment

Ichthammol and zinc cream

(chronic lichenified eczema)

Yes No

Topical glucocorticosteroid (systemic if exfoliative) Continue till improved

Yes

Healing?

No

Consider UVB, PUVA, azathioprine, ciclosporin, mycophenolate mofetil SPECIALISTSONLY

Inflamed?

Figure 51.2:Pathway for treatment of

dermatitis.