What are the key differences in the management of acute versus chronic angioedema in primary care?

The management of acute versus chronic angioedema in primary care differs primarily in the urgency of intervention, duration of treatment, and the threshold for specialist referral ¹.

Acute Angioedema Management

• If symptoms are rapidly developing without anaphylaxis, immediate administration of intravenous (IV) or intramuscular (IM) chlorphenamine and hydrocortisone is recommended, followed by emergency admission ¹. This rapid response aims to reduce the risk of a severe anaphylactic reaction ¹ (Stoloff, 2010).
• For stable angioedema without anaphylaxis, the initial focus is on identifying and avoiding the underlying cause, such as stopping an angiotensin-converting enzyme (ACE) inhibitor if implicated ¹.
• Treatment typically involves offering a non-sedating oral antihistamine (e.g., cetirizine, fexofenadine, or loratadine) for up to 6 weeks ¹.
• If symptoms are severe, a short course of an oral corticosteroid (e.g., prednisolone 40 mg daily for up to 7 days) may be given in addition to the non-sedating oral antihistamine ¹.
• Patients should be advised to seek immediate medical help (dial 999 or attend A&E) if symptoms progress rapidly or if signs of anaphylaxis develop ¹.
• Review of the patient is crucial to assess treatment response ¹.

Chronic Angioedema Management

• If symptoms are likely to be persistent or recurrent, daily antihistamine treatment is prescribed for 3–6 months, followed by a review ¹.
• For individuals with a long history of urticaria and angioedema, daily antihistamine treatment may be extended for 6–12 months, with gradual withdrawal ¹.
• If symptoms were short-lived and frequent recurrence is unlikely, treatment can be taken as required or prophylactically ¹.
• Referral to a dermatologist or immunologist is a key difference for chronic cases ¹. This is indicated if hereditary or acquired angioedema is suspected, symptoms persist or recur 3 months after stopping an ACE inhibitor, or the cause of angioedema is unidentifiable or unavoidable ¹. Hereditary and acquired angioedema are not histamine-mediated and hence do not respond to antihistamines or corticosteroids ¹ (Tachdjian, 2021; BMJ, 2016; BNF, 2022).
• If there is no improvement or symptoms worsen on treatment, hospital admission should be considered ¹. While specialist guidelines suggest incremental updosing of antihistamines, CKS recommends considering hospital admission due to increased risk of anaphylaxis ¹.

General Considerations for Both

• The overall management depends on the cause, duration, and severity of the angioedema ¹ (Powell, 2015; BMJ, 2016).
• Angioedema with urticaria is typically mast cell or histamine mediated and responds well to trigger avoidance, oral antihistamines, and corticosteroids ¹ (Powell, 2015; BMJ, 2016).
• Drug-induced angioedema necessitates identifying and stopping the responsible drug ¹. However, the efficacy of antihistamines, corticosteroids, and adrenaline for this type remains unproven ¹ (Powell, 2015; BMJ, 2016).
• Patients at risk of anaphylaxis, such as those with co-existing asthma, COPD, or heart disease, or those who have experienced angioedema with trace amounts of an allergen, should have specialist advice sought regarding an adrenaline auto-injector device ¹. After emergency treatment for suspected anaphylaxis, referral to a specialist allergy service is essential ².
• Providing comprehensive information about angioedema and its management is important for all patients ¹,³.