What is the treatment for angioedema caused by lisinopril (angiotensin-converting enzyme inhibitor)?

Treatment for Lisinopril-Induced Angioedema

The first-line treatment for lisinopril-induced angioedema is immediate discontinuation of lisinopril and all other ACE inhibitors for the lifetime of the patient, along with appropriate airway management based on severity. 1

Immediate Management Algorithm

1. Assess Airway Status:

   • Mild (face, lips only): Close monitoring
   • Severe (tongue, floor of mouth, glottis): Secure airway immediately via intubation
   • Life-threatening: Consider emergency surgical airway if intubation not possible

2. Pharmacological Management:

   • Administer antihistamines (e.g., diphenhydramine 50mg IV)
   • Administer corticosteroids (e.g., methylprednisolone or hydrocortisone 100mg IV)
   • Consider epinephrine for severe cases (subcutaneous or inhaled)

3. Monitoring:

   • Continuous monitoring until complete resolution
   • Angioedema typically resolves within 24-72 hours after ACE inhibitor discontinuation

Important Considerations

Mechanism and Risk Factors

ACE inhibitor-induced angioedema results from defective degradation of vasoactive peptides including bradykinin, which can directly or indirectly cause angioedema 2. The risk is higher in:

• Black patients
• Patients taking concomitant mTOR inhibitors or neprilysin inhibitors 1

Future Antihypertensive Therapy

After experiencing ACE inhibitor-induced angioedema:

• Never restart any ACE inhibitor - this is a lifelong contraindication 2
• Use caution with ARBs - while ARBs may be considered as alternative therapy, some patients have also developed angioedema with ARBs 2
• Wait period before ARB initiation - if an ARB is considered, wait at least 6 weeks after ACE inhibitor discontinuation 2

Common Pitfalls to Avoid

1. Delayed airway intervention - Early intubation in patients with tongue or laryngeal involvement can prevent emergency surgical airways 3

2. Restarting ACE inhibitors - Even if the initial episode was mild, recurrent episodes can be more severe and potentially fatal 4

3. Immediate ARB substitution - Due to cross-reactivity risk, extreme caution is advised when substituting an ARB 2

4. Underestimating severity - Angioedema can progress rapidly and become life-threatening; close monitoring is essential even in seemingly mild cases 4

5. Overlooking contributing factors - Renal dysfunction and dehydration may precipitate angioedema in patients previously tolerating ACE inhibitors 5

The treatment of lisinopril-induced angioedema is primarily supportive with focus on airway management. Unlike allergic reactions, this is a bradykinin-mediated process, which explains why traditional treatments like antihistamines and steroids may have limited efficacy but are still commonly used in clinical practice.