Abstract
Hydralazine is a vasodilator medication commonly used for treating hypertension. While generally well-tolerated, in rare cases it can induce autoimmune reactions, including anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. This case report presents a patient who developed ANCA-associated vasculitis resulting in crescentic glomerulonephritis (CrGN) following long-term hydralazine therapy, highlighting the importance of considering this rare adverse effect in patients with unexplained renal decline.