Hydralazine Dosing Guidelines for Heart Failure and Hypertension

Introduction to Hydralazine Therapy

• The American College of Cardiology recommends starting hydralazine at 37.5 mg three times daily (in combination with isosorbide dinitrate 20 mg three times daily) for heart failure with reduced ejection fraction, titrating to a target of 75 mg three times daily 1, 2

Heart Failure Dosing

• For heart failure with reduced ejection fraction, the initial dose is 37.5 mg hydralazine + 20 mg isosorbide dinitrate three times daily, with a target dose of 75 mg hydralazine + 40 mg isosorbide dinitrate three times daily 1, 2, 3
• The European Heart Journal suggests a titration schedule with dose increases after 2-4 weeks if tolerated and no symptomatic hypotension 3

Critical Monitoring Points

• The American College of Cardiology advises checking blood pressure before each dose escalation 4
• Monitor for symptomatic hypotension (dizziness, lightheadedness) and drug-induced lupus syndrome (arthralgia, muscle aches, joint swelling, pericarditis, pleuritis, rash, fever), and check ANA if suspected 3

Hypertension Dosing

• The American College of Cardiology recommends hydralazine as a step 5 agent for resistant hypertension, starting at 25 mg three times daily and titrating to a maximum of 100-200 mg daily in divided doses 1, 5
• Hydralazine should not be used as first-line therapy for hypertension due to unpredictable response and prolonged duration of action 5, 6

Contraindications and Precautions

• The American College of Cardiology states that hydralazine is not a desirable first-line agent for acute blood pressure treatment and should not be used in patients with blood pressure <140/90 mmHg or diastolic blood pressure <60 mmHg 5, 6
• Hydralazine causes reflex tachycardia and sodium/water retention, and should always be used with a beta-blocker and diuretic 5, 4

Drug-Induced Lupus Risk

• The risk of drug-induced lupus increases significantly at doses >200 mg daily, and patients should be monitored for arthralgia, myalgia, joint swelling, pericarditis/pleuritis, rash, or fever 5, 4, 3

Hydralazine Dosing for Heart Failure

Introduction to Hydralazine Therapy

• In cases of ACE-inhibitor and ARB intolerance, the hydralazine/nitrate combination can be used as an alternative, as suggested by the European Heart Journal 7