Hydrochlorothiazide is usually prescribed for high blood pressure, but it also treats diabetes insipidus, helps prevent kidney stones, and reduces fluid retention for patients with chronic heart failure. Diuretics such as HCTZ are often called water pills because they encourage elimination of excess water and salt, explains WebMD.
Patients taking HCTZ can expect to urinate more frequently. To reduce sleep interruption, HCTZ should not be taken within four hours of bedtime. Dizziness or lightheadedness may occur, particularly when transitioning to standing after sitting or lying down, but moving through transitions slowly helps counteract unsteadiness. Patients need to monitor themselves for signs of dehydration, including dry mouth, excessive thirst and unusually infrequent urination, according to WebMD.