What is the treatment for angioedema?

Treatment of Angioedema

The treatment of angioedema should be based on its classification as either histamine-mediated or bradykinin-mediated, with immediate assessment for airway compromise being the first priority in all cases. 1

Initial Assessment and Emergency Management

1. Immediate airway assessment

   • Evaluate for signs of airway compromise
   • Consider early elective intubation if signs of impending airway closure develop
   • High-risk features requiring closer monitoring: edema involving larynx, palate, floor of mouth, or oropharynx with rapid progression (within 30 minutes) 1
   • All patients with oropharyngeal or laryngeal angioedema should be observed in a facility capable of emergency airway management 1
   • Monitor oxygen saturation to maintain levels above 92% 1

2. Classification of angioedema (determines treatment approach)

   • Histamine-mediated (usually presents with urticaria/hives)
   • Bradykinin-mediated (no urticaria, includes HAE, acquired C1 inhibitor deficiency, and ACE inhibitor-associated angioedema) 1

Treatment Based on Classification

Histamine-Mediated Angioedema

1. First-line treatment:

   • H1 antihistamines (cetirizine, desloratadine, fexofenadine) 1
   • Add H2 antihistamines (famotidine) for better control 1
   • If severe allergic reaction history exists, administer epinephrine promptly 1

2. Second-line treatment:

   • Corticosteroids for more severe cases (methylprednisolone 125 mg IV) 1

Bradykinin-Mediated Angioedema

1. Hereditary Angioedema (HAE) acute attacks:

   • Icatibant: 30 mg subcutaneously in the abdominal area 1, 2
     • May repeat at 6-hour intervals if needed
     • Maximum 3 injections in 24 hours 1, 2
   • C1 esterase inhibitor concentrate: 20 IU/kg IV 1
   • Ecalantide (plasma kallikrein inhibitor) 1

2. ACE inhibitor-induced angioedema:

   • Discontinue the ACE inhibitor immediately 3
   • Supportive care and airway management
   • Icatibant may be effective 1, 4

3. Abdominal attacks:

   • May require narcotic pain medication
   • Antiemetics
   • Aggressive hydration 1

Long-Term Prophylaxis for Recurrent HAE

• Plasma-derived C1INH replacement
• Lanadelumab
• Attenuated androgens (Danazol: 100 mg alternate days to 600 mg daily)
• Tranexamic acid (30-50 mg/kg/day in 2-3 divided doses, maximum 3 g/day) 1

Special Considerations

• Elderly patients: Show increased systemic exposure to icatibant 2
• Pregnancy: Hydroxyzine is contraindicated during early pregnancy 1
• Women with HAE: Avoid estrogen-containing contraceptives 1
• Higher risk groups for ACE inhibitor-induced angioedema: African Americans, people over 65, women, and those with smoking history 1

Common Pitfalls and Caveats

1. Misdiagnosis of abdominal attacks: HAE abdominal attacks are frequently misdiagnosed, leading to unnecessary surgical interventions 1

2. Delayed diagnosis: Average delay in diagnosis of HAE is significant; early identification is crucial 1

3. Treatment mismatch: Using antihistamines and corticosteroids for bradykinin-mediated angioedema is ineffective 4

4. Medication review: Always check if patient is taking ACE inhibitors or angiotensin receptor blockers, as these are common causes of angioedema 5

5. Patient education: Essential components include:

   • Early recognition of attacks
   • Emergency action plans
   • Home access to appropriate medications
   • Medical alert identification 1

By following this structured approach to angioedema treatment based on proper classification and timely intervention, clinicians can effectively manage this potentially life-threatening condition while minimizing morbidity and mortality.