From the Guidelines
The recommended oral dose of hydralazine for hypertension is 100-200 mg, taken 2 or 3 times daily. This dosage is based on the most recent and highest quality study available, which is 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. It's essential to note that hydralazine is associated with sodium and water retention and reflex tachycardia, so it's often used in combination with a diuretic and a beta-blocker to enhance its antihypertensive effect and minimize side effects. Some key points to consider when prescribing hydralazine include:
- Monitoring for drug-induced lupus-like syndrome, especially at higher doses
- Potential for orthostatic hypotension, especially in older adults
- Importance of consistent dosing with respect to meals to maintain steady blood levels
- Common side effects such as headache, palpitations, and tachycardia
- Need for gradual dose titration to minimize side effects and optimize blood pressure control. It's crucial to weigh the benefits and risks of hydralazine in the context of individual patient factors, such as comorbidities, age, and concomitant medications, to ensure optimal management of hypertension and minimize adverse effects.
From the Research
Oral Dose of Hydralazine for Hypertension
- The recommended oral dose of hydralazine for hypertension varies depending on the patient's response and acetylator status 2.
- A study found that the daily dose of hydralazine that elicited 50% of the maximum response (D50) was 0.87 mg/kg for slow acetylators and 1.68 mg/kg for fast acetylators 2.
- Another study compared the efficacy of different hydralazine regimens, including 100 mg twice daily and 200 mg once daily, and found that twice-daily conventional hydralazine and once-daily slow-release hydralazine gave satisfactory control for 24 hours in both rapid and slow acetylators 3.
- The dose of hydralazine required can range from 75 mg to 200 mg per day, according to patient response 4.
- A combination of propranolol and hydralazine was found to be safe and more effective than either component alone, with daily doses of propranolol/hydralazine ranging from 40 mg/25 mg to 160 mg/100 mg 5.
- A single oral dose of 50 to 100 mg of hydralazine was found to produce sustained hemodynamic improvement in patients with left ventricular failure 6.