Diagnosis of Lisinopril-Induced Small Bowel Angioedema After a Seven-Year Diagnostic Journey: A Case Report With Patient Perspective

Angiotensin-converting enzyme inhibitors (ACEIs) are widely prescribed for managing hypertension and improving cardiovascular and renal health while being relatively low-cost and generally well-tolerated. ACEI-induced angioedema is an uncommon but potentially serious adverse effect that may present with swelling of the face, lips, tongue, and pharynx, raising concern for possible airway obstruction, hypoxia, and even death. Other presentations have been documented, including small bowel angioedema (SBAE). SBAE is diagnostically challenging due to its nonspecific gastrointestinal symptoms. This report highlights a middle-aged woman who experienced ACEI-induced SBAE for nearly seven years alongside comorbid conditions. Despite extensive evaluations for gastrointestinal pathologies, her condition remained unresolved until a multidisciplinary team attributed her symptoms to ACEI therapy. Upon discontinuing lisinopril, her symptoms resolved, emphasizing the importance of recognizing drug-induced causes in patients with unexplained, persistent symptoms. This case underscores the critical role of the healthcare team in identifying and managing adverse drug reactions (ADRs), especially with common medications like ACEIs. Clinicians may utilize readily available assessment tools to help identify possible ADRs. A multidisciplinary approach is essential, as physicians across specialties are uniquely positioned to recognize potential ADRs and communicate concerns collaboratively. Early detection can reduce unnecessary hospitalizations and interventions and improve patient outcomes.