Urticaria (Hives)

INTRODUCTION

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Can be classified as:

• papular (hives) (e.g. insect bites): papules tend to persist

• giant cell

  • – widespread weals: tend to ‘come and go’

  • – superficial—dermis = urticaria

  • – deep—subcutaneous = angioedema

CHECK CAUSES

• Food: nuts, esp. peanuts, chocolate, cheese, fish, eggs, etc.

• Drugs (e.g. aspirin, antibiotics)

• Infections (e.g. viruses—most common in children; bacteria; parasites; yeasts)

• Plants: nettles, Grevillea, Rhus

• Physical: exercise and heat, cold

• Unknown aetiology in most cases (up to 80%)

Treatment

• Avoid any identifiable causes

• Antihistamines, e.g. cyproheptadine 16–32 mg (o) daily, non-sedating (e.g. cetirizine, loratadine, fexofenadine)

• Lukewarm baths with Pinetarsol or similar soothing bath oil

• Topical soothing preparation (e.g. crotamiton 10% or phenol 1% in oily calamine or menthol 1% cream)

• If severe (avoid if possible): prednisolone 50 mg once daily for 10 d; symptoms often return upon cessation

• Consider specialist referral if symptoms persist >6 wks