What is the recommended dose and frequency of hydralazine (direct vasodilator) for treating hypertension?

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From the Guidelines

The recommended dose of hydralazine for treating hypertension is 100-200 mg daily, administered in 2 or 3 doses, as per the 2018 ACC/AHA guideline 1.

Key Considerations

  • Hydralazine is a direct vasodilator that works by relaxing vascular smooth muscle, primarily in arterioles, which reduces peripheral resistance and lowers blood pressure.
  • Due to its association with sodium and water retention and reflex tachycardia, hydralazine should be used in combination with a diuretic and beta-blocker.
  • The dose may need to be adjusted based on patient response and tolerance, with careful monitoring for potential side effects such as headache, tachycardia, fluid retention, and lupus-like syndrome with long-term use.

Dosing and Administration

  • The usual dose range for hydralazine is 100-200 mg daily, divided into 2 or 3 doses.
  • Patients should be monitored regularly to assess efficacy and guide dose adjustments.
  • Hydralazine can be used in combination with other antihypertensive agents, such as beta-blockers and diuretics, to achieve optimal blood pressure control.

Special Considerations

  • In patients with resistant hypertension, hydralazine may be considered as a fifth-line agent, after other options such as spironolactone, eplerenone, and beta-blockers have been tried 1.
  • Hydralazine should be used with caution in patients with renal impairment or elderly patients, and the dose may need to be adjusted accordingly.

Monitoring and Follow-up

  • Patients taking hydralazine should be monitored regularly for potential side effects and to assess efficacy.
  • Blood pressure should be checked regularly to guide dose adjustments and ensure optimal blood pressure control.
  • Patients should be educated on the importance of adherence to their medication regimen and lifestyle modifications to achieve optimal blood pressure control.

From the FDA Drug Label

The usual recommended oral starting dosage is 0.75 mg/kg of body weight daily in four divided doses. Dosage may be increased gradually over the next 3 to 4 weeks to a maximum of 7. 5 mg/kg or 200 mg daily. The recommended dose and frequency of hydralazine for treating hypertension is:

  • Starting dose: 0.75 mg/kg of body weight daily in four divided doses
  • Maximum dose: 7.5 mg/kg or 200 mg daily 2

From the Research

Recommended Dose and Frequency of Hydralazine for Hypertension

  • The recommended dose and frequency of hydralazine for treating hypertension is not explicitly stated in the provided studies 3, 4, 5, 6, 7.
  • However, it is mentioned that hydralazine is a vasodilator that can be used as a reserve medication, and its withdrawal should be considered in individual cases 3.
  • In general, treatment of arterial hypertension should be initiated with a long-acting drug at a low dose, and doses should only be slowly increased under close blood pressure control 3.
  • The use of low-dose combination therapy for initial treatment of hypertension is being increasingly investigated and recommended, as it provides more effective blood pressure lowering with fewer adverse events 5, 6.
  • The studies suggest that initiating treatment with combination blood pressure lowering therapy can be an effective approach, but the specific dose and frequency of hydralazine are not provided 4, 5, 6.

Key Considerations

  • The dose-response curve for antihypertensive drugs is usually very flat, while adverse effects may rise disproportionately with higher doses 3.
  • Modern antihypertensive drugs can be abruptly and safely withdrawn in most patients, but a gradual dose taper may be necessary in certain cases 3.
  • The treatment approach should be individualized, taking into account the patient's specific needs and medical history 3, 4, 5, 6, 7.

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Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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