A Textbook of Clinical Pharmacology and Therapeutics

DERMATITIS (ECZEMA)
PRINCIPLES OF TREATMENT
Avoid precipitating factors
Emollients
Dry, fissuring Weeping, exudating
Aqueous cream
Emulsifying ointment
Ichthammol and zinc cream
(chronic lichenified eczema)
Yes No
Inflamed?
The most common forms of dermatitis that present to physicians
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 glucocorticosteroids.
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.
Ichthammol and zinc cream may be used in chronic lichenified
forms of eczema. Potassium permanganate solution can
be used in exudating eczema for its antiseptic and astringent
effect; treatment should be stopped when weeping stops.
Potassium permanganate solution
Antibiotics (if secondary infection)
Topical glucocorticosteroid (systemic if exfoliative) Continue till improved
Healing?
No
Yes
Consider UVB, PUVA, azathioprine, ciclosporin, mycophenolate mofetil
SPECIALISTS
ONLY
DERMATITIS (ECZEMA) 413
Figure 51.2: Pathway for treatment of
dermatitis.
Weeping eczema may require topical glucocorticosteroids and
often antibiotics to treat secondary infection. Immunosuppressant
therapy, such as ciclosporin, is sometimes effective in
severe, resistant eczema. Ultraviolet B or psoralen � ultraviolet
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 glucocorticosteroid.
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 vasoconstrictors
and reduce keratinocyte proliferation. They include
hydrocortisone and its fluorinated semi-synthetic derivatives,
which have increased anti-inflammatory potency compared to
hydrocortisone (Chapter 40).