renal calculus †
† non-FDA-approved indication
Hydrochlorothiazide, HCTZ (Microzide) Indications and Dosage
For the treatment of hypertension:
Oral dosage:
Adults and Adolescents: Initially, 12.5 - 25 mg PO once daily. Dosage may be increased, if necessary, up to 50 mg/day PO given in 1 - 2 divided doses. Although the manufacturer’s recommended maintenance dosage is 25 - 100 mg PO per day, expert panels on the treatment of hypertension recommend the addition of another antihypertensive agent if blood pressure is not controlled with 25 - 50 mg/day of hydrochlorothiazide. In a double-blind randomized study, the effects of 25 mg/day vs. 50 mg/day of hydrochlorothiazide were evaluated in elderly patients (n=51) with isolated systolic hypertension. Both dosages were associated with similar reductions in blood pressure; however, the higher dose (50 mg/day) caused a greater decline in serum potassium concentration.
Elderly: See adult dosage. Elderly patients may be more sensitive to the effects of the usual adult dosage.
Children and infants > 6 months: 2 mg/kg/day PO, given in 2 divided doses is the usual dosage recommended by one pediatric dosage source; however, 3 mg/kg/day PO is the highest dosage recommended by the manufacturer.
Infants < 6 months and neonates: 2 - 4 mg/kg/day PO, given in 2 divided doses is the usual dosage recommended by one pediatric dosage source; however, 3 mg/kg/day PO is the highest dosage recommended by the manufacturer.
For use as an adjunctive agent to treat peripheral edema associated with congestive heart failure, hepatic cirrhosis (ascites), corticosteroid therapy, or estrogen therapy; or to treat edema associated with renal dysfunction † including nephrotic syndrome, acute glomerulonephritis † , and chronic renal failure † :
Oral dosage:
Adults and Adolescents: 25 - 100 mg/day PO, given in single or divided doses. Many patients with edema respond to intermittent therapy (e.g., every other day or 3 - 5 days each week).
Elderly: See adult dosage. Elderly patients may be more sensitive to the effects of the usual adult dosage.
Children and infants > 6 months: 2 mg/kg/day PO, given in 2 divided doses is the usual dosage recommended by one pediatric dosage source; however, 3 mg/kg/day PO is the highest dosage recommended by the manufacturer.
Infants < 6 months and neonates: 2 - 4 mg/kg/day PO, given in 2 divided doses is the usual dosage recommended by one pediatric dosage source; however, 3 mg/kg/day PO is the highest dosage recommended by the manufacturer.
For the treatment of nephrogenic or central diabetes insipidus † :
Oral dosage:
Adults: 50 - 100 mg/day PO has been used.
Elderly: See adult dosage. Elderly patients may be more sensitive to the effects of the usual adult dosage.
For the prevention of nephrolithiasis † (calcium-containing renal calculus † ) due to hypercalciuria † :
Oral dosage:
Adults: 50 mg PO, given 1 - 2 times per day, has been used.
Elderly: See adult dosage. Elderly patients may be more sensitive to the effects of the usual adult dosage.
For the treatment of symptoms of bloating and weight gain associated with premenstrual syndrome (PMS) † :
Oral dosage:
Adults: 25 - 50 mg PO, given once daily or twice daily. Diuretic use should be limited to patients who demonstrate a premenstrual weight gain of > 1.4 kg. Dosages should be individually titrated to achieve desired diuresis and decreased weight gain.
Maximum Dosage Limits:
