Spontaneous urticaria and/or angiodema

Urticaria and angioedema may be seen in allergic reactions but may also occur spontaneously or secondary to other medical conditions.


History and Examination

Clinical history/examination suggestive of urticarial/angioedema, see Patient.co.uk - chronic-urticaria-hives

Clinical history to exclude allergy; has the patient been exposed to a trigger (e.g. food, drug, sting, latex) before each episode? Typically allergic reactions will occur within minutes after exposure to an allergic trigger. If associated with respiratory involvement or collapse/faintness see anaphylaxis guideline.

If history suggests food, drug, sting or latex allergy (in the absence of anaphylaxis) please click for appropriate guideline

If Angioedema but no history of urticaria check complement C4 (to exclude C1 Inhibitor deficiency (hereditary or acquired angioedema)

ACE inhibitor treatment can cause angioedema and must be stopped in patients presenting with angioedema

A detailed history and examination to exclude underlying pathology (e.g. infection) should be undertaken. Check Thyroid function (given association between thyroid dysfunction and spontaneous urticarial/angioedema).

Spontaneous urticarial/angioedema occurs in the absence of allergic triggers, in some patients there may be exacerbating factors (e.g. heat, cold, pressure) see Patient.co.uk/health/physical-urticaria...


Spontaneous (Idiopathic) Angioedema can be treated with non sedating antihistamines

Treatment may be as required or prophylactic depending on frequency of symptoms. Higher than licensed doses may be required (e.g. cetirizine 10mg up to 4 times a day (BSACI Guidelines), these increased doses must not be used in pregnancy, and attention should be paid to interactions with other drugs.

Airway involvement is rare, patients should be aware that if airway angioedema (symptomatic breathlessness or throat tightening) occurs they should contact emergency services via 999.

Swelling involving the mouth/tongue can cause patients considerable concern. If tongue swelling is mild advise treatment with high dose antihistamines, a single dose of prednisolone 20-30mg may be used however long term regular corticosteroids are not advised. If throat tightening/breathlessness/voice change advise patients to contact emergency medical services via 999 (refer to specialist allergy clinic)

All patients with angioedema should avoid ACE inhibitors

Patients with urticaria and/or angioedema should be advised to use NSAIDS with caution.

Guidelines for the management of chronic urticaria and agiodema

Patient management plan local latex guidelines,

National guidance on the management of Urticaria


Referral Criteria

Refer to clinical allergy/immunology:

  • Patients with troublesome symptoms (rash or swelling) despite high doses of non-sedating antihistamines for at least a month (see above for guidance).
  • If swelling involves the airway e.g. sensation of breathlessness, throat tightening, voice change
  • If there is diagnostic uncertainty
  • Patients with angioedema and a low C4

Referral instructions

Refer to Clinical Immunology Service
  • Refer using e-Referral Service
    • Specialty: Allergy
    • Clinic type: Allergy
    • Service: DRSS-Northern-Allergy- Devon CCG- 15N

Referral form

DRSS Referral forms

Supporting Information


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