Aliskiren Hemifumarate is primarily used in the treatment of hypertension, or high blood pressure. It works by inhibiting renin, an enzyme that plays a crucial role in regulating blood pressure. By blocking renin, it reduces the production of angiotensin I and II, leading to vasodilation and decreased blood pressure. This makes it effective for patients who require long-term management of hypertension, including those who may not respond adequately to other antihypertensive medications. It is often prescribed as a monotherapy or in combination with other drugs like diuretics or calcium channel blockers to enhance its efficacy. Additionally, it is sometimes used in patients with heart failure or kidney disease, where controlling blood pressure is critical to slowing disease progression. Its oral administration and once-daily dosing make it convenient for patient adherence.