The treatment of angioedema will depend on its subtype. In acute severe instances treatment is provided by A&E, Intensive Care or Ear, Nose & Throat departments. In acute instances of angioedema of the airways, keeping the airways clear is paramount. If the airways are threatened, intubation should be carried out as soon as possible, as emergency tracheostomy may otherwise be required. The favoured option will often be awake nasal intubation guided by a flexible nasendoscope. Due to the risk of aspiration, an oral airway should never be used to maintain clear airways on patients who are awake.
Despite limited evidence, medical treatment of acute histaminergic angioedema consists of antihistamine i.v./i.m. (adults e.g. Tavegyl 1 – 2 mg), intravenous corticosteroid (adults e.g. Solu-Medrol 80 – 120 mg) and, for laryngeal edema, inhalation of nebulised adrenaline at 5 – 10 litres oxygen/min (adrenaline 1 mg in 5 ml NaCl) and possibly intramuscular adrenaline (always in cases of anaphylactic shock) (39). Bradykinergic angioedema in the acute phase may be treated with C1INH concentrate (Berinert, Cinryze, Ruconest) or bradykinin receptor-2 antagonist icatibant (Firazyr) (9, 10, 32, 40, 41). For this group of patients adrenaline is not effective, or only marginally/briefly effective and may trigger unnecessary and sometimes severe side effects involving tachycardia, hypertension, arrhythmia and a risk of cerebral and cardiac insult (felleskatalogen.no).
Angioedema caused by infection are addressed by treating the underlying infection.
In their chronic phases histaminergic angioedema can be treated with non-sedating antihistamines, the doses of which may be increased when disease control is suboptimal, or combined with a leukotriene receptor antagonist (montelukast, limited evidence) or H2 antagonist (limited evidence). Immune modulation or immunosuppressant therapies are used in certain treatment-resistant cases, e.g. cyclosporine, azathioprine or methotrexate (2) – (4, 11). Similarly, anti-inflammatory drugs and antibiotics such as sulphasalazine, dapsone and hydroxychloroquine are used with varying degrees of effect and evidence (4, 11). Systemic corticosteroids are often effective, but due to their long-term side effects should be used only briefly in case of flare-ups or when acute treatment is required (3) – (5, 11). Plasmapheresis and intravenous immunoglobulin are used in rare cases (3) – (5). In clinical trials and off-label at the clinic omalizumab is used for the treatment of both chronic urticaria and histaminergic angioedema with good effect. As yet, the drug is approved only for the treatment of asthma (42).
Angioedema triggered by specific drugs, foods or physical stimuli is treated by trying to eliminate the trigger factor. Patients with ACE inhibitor-induced angioedema may go on to angiotensin II-receptor blockers (24). Long-term treatment with tranexamic acid or weak androgens (e.g. danazol) may be used for chronic bradykinergic angioedema and idiopathic angioedema (3, 10, 43, 44).
Follow-up and treatment of patients with chronic angioedema are often conducted by the GP, an allergologist, pulmonary specialist or dermatologist. Patients whose angioedema has a systemic cause are followed up and treated by medical specialists, e.g. within the fields of rheumatology, endocrinology (thyroid disease), pulmonary medicine or paediatrics. Educating the patient forms a significant part of the treatment (4).