Hydrochlorothiazide for High Blood Pressure

Hydrochlorothiazide (HCTZ) is a prescription medication approved for several different uses. It is commonly used to treat water retention caused by estrogen and corticosteroids. Healthcare providers also often prescribe hydrochlorothiazide for high blood pressure.

A blood pressure reading consists of two numbers -- for example: 120/80. The top number is known as the systolic blood pressure, and the bottom number is the diastolic blood pressure. High blood pressure is defined as an average blood pressure higher than 140/90, with multiple blood pressure readings.

Based on clinical studies, hydrochlorothiazide has been shown to significantly lower both systolic and diastolic blood pressure. By lowering blood pressure, the medication can also decrease the risk of developing health problems (such as a stroke, heart disease, or congestive heart failure) that occur with long-term high blood pressure (see Effects of High Blood Pressure).

Hydrochlorothiazide is not a cure for high blood pressure.

(Click What Is Hydrochlorothiazide Used For? for information on how hydrochlorothiazide works for high blood pressure, to learn about other approved uses for this drug, and to find out if it is used for off-label purposes.)