Enalapril-Induced, Near-Fatal Angioedema

Abstract

Objective: To report a near-fatal angioedema associated with the use of enalapril, a long-acting angiotensin-converting enzyme inhibitor. Data Sources: Medical record of the patient, case reports identified by MEDLINE. Case Summary: A 52-year-old man was admitted to our institution for closed reduction and debridement of an injury sustained to the left index finger. The patient's blood pressure was increased (180/102 mm Hg), and he was placed on nifedipine 60 mg and enalapril 5 mg/d. Other medications included ranitidine 150 mg bid and cefotaxime 2 g q8h. Eighteen hours after the first dose of enalapril the patient developed swelling of the face and lips and had difficulty breathing. The patient was seen initially by the house physician, who ruled out a penicillin/cephalosporin allergy. The assessment of an allergic reaction to enalapril was made and the drug was discontinued. Diphenhydramine 50 mg im, epinephrine 0.5 mL sc, and methylprednisone 125 mg iv were given immediately, and the patient was transferred to the intensive care unit (ICU). Methylprednisone 100 mg q6h was initiated along with diphenhydramine 50 mg im q6h prn. Over the next 48 hours the swelling decreased and the patient was removed from the ICU. The dosage of methylprednisone was decreased to 40 mg q6h and the patient was discharged the following day. Conclusions: The pathogenesis of angiotensin-converting enzyme (ACE) inhibitor-induced angioedema is not fully understood. This unique idiosyncratic adverse drug reaction may occur even though the medication has been tolerated for months or years. The symptoms may regress quickly while the patient is still taking the medication, resulting in no diagnosis, or the symptoms may progress rapidly despite aggressive medical intervention. The rapidly expanding market of these agents along with the expected availability of generic captopril in 1995 may increase overall prescriptions written for ACE inhibitors in the US, potentially increasing the number of cases of angioedema. This patient was diagnosed quickly and resulted in a positive outcome. Physicians and other healthcare providers should be aware of the symptoms of ACE inhibitor-induced angioedema and make their patients aware as well.