GENERIC NAME: chlorthalidone
BRAND NAME: Thalitone
DISCONTINUED BRAND: Hygroton (discontinued in U.S.A.)
DRUG CLASS AND MECHANISM: Chlorthalidone is a diuretic (water pill). It works by reducing the kidneys' ability to hold on to salt and water and increasing the kidneys' production of urine (diuresis). It is used to eliminate excess salt and water from the body and to treat high blood pressure. Chlorthalidone is closely related chemically to hydrochlorothiazide. (Both are "thiazide" diuretics.). It was approved by the FDA in 1960.
SIDE EFFECTS: Chlorthalidone generally is well tolerated.
- Low blood levels of potassium, sodium, and magnesium due to increased excretion via urine.
- High blood calcium levels also can occur, especially in persons who are taking calcium supplements.
- Thiazide diuretics such as chlorthalidone increase the levels of uric acid in the blood, but gout (which is caused by high levels of uric acid) rarely occurs.
- Chlorthalidone can cause high blood sugars in patients with diabetes.
Other important side effects include:
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