Description

Aliskiren (as Hemifumarate) + Hydrochlorothiazide is a single-tablet combination medication used to treat high blood pressure (hypertension). This medication includes Aliskiren, a direct renin inhibitor, and Hydrochlorothiazide, a thiazide diuretic. This combination provides a unique and powerful way to lower blood pressure by targeting two different and complementary systems.

Indications

This combination therapy is primarily indicated for the treatment of hypertension. It is typically prescribed to:

• Patients whose blood pressure is not adequately controlled with either aliskiren or hydrochlorothiazide alone.

• As an alternative for patients who require a multi-drug approach to reach their blood pressure goals.

By effectively lowering blood pressure, this combination helps to reduce the risk of serious cardiovascular events, such as stroke, heart attack, and heart failure.

Mechanism of Action

The combination works by targeting two different and crucial systems that regulate blood pressure and fluid balance in the body.

1. Aliskiren (Direct Renin Inhibitor)

• Action: Aliskiren works on the renin-angiotensin-aldosterone system (RAAS), a hormonal pathway that is central to blood pressure regulation. Unlike ACE inhibitors or ARBs, which act further down the pathway, aliskiren works at the very beginning by directly inhibiting the enzyme renin. Renin is responsible for converting angiotensinogen into angiotensin I.

• Effect: By blocking this initial step, aliskiren prevents the entire cascade that leads to the formation of the powerful vasoconstrictor angiotensin II. This ultimately leads to vasodilation (the widening of blood vessels) and reduced fluid retention.

2. Hydrochlorothiazide (Thiazide Diuretic)

• Action: Hydrochlorothiazide, often called HCTZ, acts on the kidneys. It inhibits the reabsorption of sodium and chloride ions from the distal convoluted tubule.
• Effect: As sodium and chloride are excreted, water follows them out of the body through urine. This process reduces the total fluid volume in the bloodstream, which in turn lowers blood pressure and decreases the workload on the heart.

Combined Effect

The combination of Aliskiren and Hydrochlorothiazide provides a powerful synergistic effect:

• Aliskiren blocks the RAAS pathway at its origin, preventing the creation of vasoconstricting hormones.

• Hydrochlorothiazide reduces the body’s blood volume.

This dual action leads to a more significant and sustained reduction in blood pressure than either drug could achieve on its own, making it a highly effective treatment for hypertension.