Hydralazine Dosage

Medically reviewed by Drugs.com. Last updated on Aug 4, 2023.

Usual Adult Dose for Hypertension

Initial dose: 10 mg orally 4 times a day for the first 2 to 4 days; increase to 25 mg orally 4 times a day for the balance of the first week
Week 2 and subsequent weeks: 50 mg orally 4 times a day
Maintenance dose: Adjust dosage to the lowest effective levels

Comments:

• In resistant patients, up to 300 mg/day may be needed to acquire a significant antihypertensive effect.

Use. For the treatment of essential hypertension, alone or as an adjunct

Usual Adult Dose for Hypertensive Emergency

20 to 40 mg IM or rapid IV bolus; repeat as needed

Comments:

• Certain patients may require lower doses, especially those with marked renal damage.
• Blood pressure may begin to fall within a few minutes after injection, with the average maximal decrease occurring in 10 to 80 minutes; monitor frequently following injection.
• In situations where there has been increased intracranial pressure, lowering the blood pressure may increase cerebral ischemia.
• Most patients can be transferred to the oral formulation within 24 to 48 hours.

Use: For the treatment of severe essential hypertension when this drug cannot be given orally or when there is an urgent need to lower blood pressure

Usual Pediatric Dose for Hypertension

Oral:

• Initial dose: 0.75 mg/kg/day in 4 divided doses
• May increase gradually over 3 to 4 weeks to a maximum of 7.5 mg/kg/day or 200 mg/day

Comments:

• Safety and effectiveness have not been established in pediatric patients in controlled clinical trials, however, there is experience with use of this drug in children at the provided doses.

Use. For the treatment of essential hypertension, alone or as an adjunct

Usual Pediatric Dose for Hypertensive Emergency

Parenteral: 1.7 to 3.5 mg/kg/day IM or IV in 4 to 6 divided doses

Comments:

• Safety and effectiveness have not been established in pediatric patients in controlled clinical trials, however, there is experience with use of this drug in children at the provided doses.

Use: For the treatment of severe essential hypertension when this drug cannot be given orally or when there is an urgent need to lower blood pressure

Renal Dose Adjustments

Dose adjustments may be required; however, no specific guidelines have been suggested. Use with caution, especially in patients with advanced renal damage.

Liver Dose Adjustments

Data not available

Dose Adjustments

Slow acetylators may experience higher plasma levels and may require lower dosages or dose adjustments in order to maintain pressure.

Precautions

Safety and effectiveness have not been established in pediatric patients in controlled clinical trials, however, there is experience with use of this drug in children at the provided doses.

Consult WARNINGS section for additional precautions.

Dialysis

Data not available

Other Comments

Administration advice:

• Injectable: Use immediately after opening vial; not to be added to infusion solutions.

Storage requirements:

• Tablets: Dispense in tight, light resistant container.

Reconstitution/preparation techniques

• Injectable: Inspect visually for particulate matter and discoloration; may discolor upon contact with metal; discolored solutions should be discarded.

Monitoring:

• Cardiovascular: Monitor blood pressure frequently during IM or IV injection

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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