From the Guidelines
The dose for hydrochlorothiazide is 25-50 mg/d.
Key Points
- The usual dose range for hydrochlorothiazide is 25-50 mg/d as stated in the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1.
- This dose is recommended for the treatment of hypertension in adults, with the goal of achieving adequate blood pressure control.
- It is also noted that for optimum endpoint protection, the thiazide chlorthalidone should be administered at a dose of 12.5 to 25 mg/day (or 25–50 mg/d for hydrochlorothiazide) because lower doses are either unproven or less effective in clinical outcome trials 1.
Important Considerations
- Hydrochlorothiazide is a thiazide-type diuretic, which is more effective in lowering blood pressure when given as monotherapy or as initial agents in multi-drug regimens, especially in blacks 1.
- The dose of hydrochlorothiazide may need to be adjusted based on individual patient response and tolerance.
- It is essential to monitor patients for potential side effects, such as hyponatremia and hypokalemia, uric acid and calcium levels, when using hydrochlorothiazide 1.
From the FDA Drug Label
For Control of Hypertension: The adult initial dose of hydrochlorothiazide capsules is one capsule given once daily whether given alone or in combination with other antihypertensives. Total daily doses greater than 50 mg are not recommended. The dose for hydrochlorothiazide is one capsule given once daily, with a maximum recommended daily dose of 50 mg 2.
- The initial dose is one capsule per day.
- Total daily doses should not exceed 50 mg.
From the Research
Dose of Hydrochlorothiazide
- The usual dose of hydrochlorothiazide (HCTZ) is 12.5-25 mg daily 3
- A study compared the efficacy of HCTZ 12.5 mg daily with chlorthalidone 6.25 mg daily and found that HCTZ did not significantly reduce 24-hour ambulatory blood pressure 4
- Another study found that chlorthalidone 25 mg is more potent than HCTZ 50 mg, particularly in reducing overnight blood pressure 5
- A meta-analysis of dose-response characteristics of HCTZ and chlorthalidone found that chlorthalidone produces slightly greater reductions in systolic blood pressure and potassium than HCTZ on a milligram-per-milligram basis 6
- A study in black patients with mild to moderate hypertension found that low-dose HCTZ (12.5-25 mg daily) as monotherapy had only a moderate effect on blood pressure control and 24-hour blood pressure load, and the higher 25 mg dose was associated with significant decreases in serum potassium levels 7
Key Findings
- HCTZ is often prescribed at a dose of 12.5-25 mg daily 3, 4, 7
- The efficacy of HCTZ in reducing blood pressure and cardiovascular outcomes is debated, with some studies suggesting that it may not be as effective as other antihypertensive agents 3, 4, 6
- Chlorthalidone may be a more effective alternative to HCTZ, particularly at lower doses 4, 5, 6