Chronic Urticaria

This guideline (also available as a visual summary) is aimed at supporting clinicians in primary care to manage chronic urticaria in adults. In addition the British Association of Dermatologists has a useful leaflet on urticaria for patients

Step 1: History and Examination, Exclude Additional Pathology

Focused History

Onset, duration of symptoms (chronic urticaria is defined as more than 6 weeks of daily/near daily activity), triggers, particularly physical triggers: heat, cold, exercise, pressure, sun exposure), associated angioedema.

Examine

Check for dermographism. Lightly scratch the skin with a firm object and check for a wheal after 5 to10 minutes

Exclude

  • Drug-induced urticaria: For example, aspirin, codeine.
  • Urticarial vasculitis: Painful rather than itchy lesions, individual lesions lasting for more than 24 hours and leaving behind bruises/petechiae/purpura, associated joint pains/fever/malaise. Refer if suspected.
  • Food allergy: Can be excluded if no clear-cut temporal relationship between ingestion or contact with a particular food and onset of symptoms (usually within 60 minutes or less).
  • Rare causes of angioedema: If this is present without wheals (hereditary angioedema, acquired C1 inhibitor deficiency, ACE inhibitors, B-cell lymphoma).
  • Rare autoinflammatory syndromes: if patients have associated systemic features (fevers, joint pains, malaise). Refer if suspected.

Step 2: Investigation

  • Assess severity – sleep disruption, consider asking patient to complete Urticarial Activity Score (UAS). A score of less than 7 indicates good control, more than 28, severe disease:
  • Assess thyroid function tests and autoantibodies.
  • Do not routinely carry out blood tests unless history and examination suggestive. For example, full blood counts (FBC) to check for eosinophilia in parasitic infections, Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) if vasculitis suspected.

Step 3: Treatment

  1. Prescribe standard dose of non-sedating antihistamine to be taken daily (prophylactically, not just when wheals appear). For example: Loratidine (caution in hepatic impairment), cetirizine (caution in renal impairment), fexofenadine. Both Loratidine and Cetirizine can be purchased over the counter.
  2. If no response and no renal impairment, consider up to four times the recommended dose (unlicensed, consider using advice and guidance to guide treatment) of non-sedating anti-histamine. Continue this for 1 month before decreasing to three times a day for 1 month, then twice daily for 1 month then daily for 1 month before stopping treatment if symptoms well-controlled.
  3. If no response after consider addition of Montelukast 10mg one daily (off-label indication).
  4. If no response to above measures refer to secondary care.

      Note

      • If no response and no renal impairment, consider up to four times the recommended dose (unlicensed, consider using advice and guidance to guide treatment) of non-sedating anti-histamine. Continue this for 1 month before decreasing to three times a day for 1 month, then twice daily for 1 month then daily for 1 month before stopping treatment if symptoms well-controlled.
      • If no response after consider addition of Montelukast 10mg one daily (off-label indication).
      • If no response to above measures refer to secondary care

      Document History

      Version 1.0

      Approved April 2022