Hi, Lisinopril and hydrochlorothiazide (HCTZ) are commonly prescribed medications for high blood pressure. Both medications can have side effects, and ankle swelling is one of the known potential side effects associated with HCTZ. HCTZ is a diuretic, which means it increases urine production and helps reduce fluid retention in the body. However, in some cases, it can cause fluid imbalances that may lead to swelling in certain areas, including the ankles. Ankle swelling as a side effect of HCTZ is generally more common in older individuals and those with certain risk factors, such as a history of heart failure or kidney problems. Lisinopril, on the other hand, is an angiotensin-converting enzyme (ACE) inhibitor that helps relax blood vessels and lower blood pressure. It is less commonly associated with ankle swelling as a side effect. If you experienced ankle swelling after starting HCTZ and noticed an improvement after discontinuing it, it s possible that the HCTZ was contributing to the swelling. However, it s important to consult with your healthcare provider for an accurate diagnosis and appropriate management. Your healthcare provider can review your medical history, evaluate your symptoms, and determine the best course of action. They may suggest alternative medications or adjust your current treatment regimen to address your blood pressure management needs while minimizing side effects. If you require a personalized response, kindly use the Ask A Doctor service and post a follow-up. Take care. Hope I have answered your question. Regards, Dr. Priyanka, General & Family Physician