Paper Title
Drug-Induced Angioedema Without Urticaria: A Prospective Case Series of Twenty Patients

Abstract
Background Drug-induced angioedema without urticaria is a potentially life-threatening adverse drug reaction characterized by localized swelling of the skin and submucosal tissues. Although most cases resolve with prompt recognition and treatment, airway involvement may result in significant morbidity and mortality. Several drug classes including angiotensin-converting enzyme inhibitors (ACEIs), thrombolytic agents, non-steroidal anti-inflammatory drugs (NSAIDs), antibiotics, and antidiabetic medications have been implicated in the development of angioedema. Recent pharmacovigilance studies have identified ACEIs among the drugs with the strongest association with angioedema, while NSAIDs and antibiotics remain important contributors to drug-induced cases [1,2]. Aim and objective To describe the clinical characteristics, causative medications, management, and outcomes of patients presenting with drug-induced angioedema without urticaria. Methods This prospective observational case series included 20 consecutive patients presenting with drug-induced angioedema without urticaria. Patients were prospectively identified and followed after diagnosis. Clinical history, suspected offending drug, site of involvement, treatment, and outcomes were documented. Results Twenty patients were included. ACEI-associated angioedema accounted for half of all cases (10/20, 50%). Facial and lip swelling was present in all patients. Urticaria was absent in all cases. Immediate withdrawal of the suspected offending drug was undertaken in all patients. Treatment consisted of standard supportive measures including corticosteroids and antihistamines as clinically indicated. All patients recovered successfully without mortality. No patient required surgical airway intervention. Conclusion Drug-induced angioedema without urticaria is an important adverse drug reaction encountered in routine clinical practice. ACE inhibitors represented the most common causative agents in this series, followed by thrombolytic agents, NSAIDs, antibiotics, beta-blockers, and antidiabetic therapy. Early recognition, prompt discontinuation of the offending medication, and appropriate treatment resulted in favorable outcomes in all patients. Clinicians should maintain a high index of suspicion when evaluating isolated facial or lip swelling in patients receiving these medications. Keywords - Angioedema; Drug-Induced Angioedema; Enalapril; Ramipril; Tenecteplase; Diclofenac; Amoxicillin; Sitagliptin; Adverse Drug Reaction