Hydralazine Pediatric Dose — Hypertensive Urgency
Hydralazine is a direct-acting arterial vasodilator that reduces systemic vascular resistance by relaxing vascular smooth muscle. It is used in pediatric patients for the acute management of hypertensive urgency when rapid blood pressure reduction via the intravenous route is indicated. Hydralazine has a well-established role in pediatric hypertension management, particularly in inpatient and intensive care settings.
Pediatric Dosing
The recommended intravenous dose for hypertensive urgency is 0.1–0.2 mg/kg/dose every 1–2 hours IV as needed (PRN). The maximum single dose is 20 mg IV.
- Route: Intravenous (IV)
- Dose: 0.1–0.2 mg/kg/dose
- Frequency: Every 1–2 hours PRN
- Maximum single dose: 20 mg IV
Worked example — 20 kg child: 20 kg × 0.1 mg/kg = 2 mg (low end); 20 kg × 0.2 mg/kg = 4 mg (high end) per dose. Worked example — 70 kg adolescent: 70 kg × 0.2 mg/kg = 14 mg per dose (does not exceed the 20 mg maximum). Note: Renal consultation is required in non-ICU patients.
Indications and Clinical Context
Hydralazine is indicated for the acute treatment of hypertensive urgency in pediatric patients, including those with hypertension secondary to renal disease, which is among the most common causes of severe hypertension in children. It is classified as a cardiovascular emergency agent. Its direct vasodilatory mechanism provides predictable blood pressure lowering, making it a useful option when rapid but controlled reduction in blood pressure is required in the inpatient setting.
Given the significant prevalence of renal etiologies underlying pediatric hypertensive urgency, a nephrology or renal consultation is required for all non-ICU patients receiving this agent. Clinicians should identify and address underlying causes while initiating antihypertensive therapy, in accordance with standard pediatric hypertension management guidelines.
Administration and Monitoring
Hydralazine should be administered intravenously in monitored settings. Doses may be given as a slow IV push; consult institutional protocol for specific infusion guidance and dilution requirements. The maximum single dose is 20 mg IV; doses should not exceed this threshold regardless of weight-based calculation. Blood pressure should be monitored continuously or at frequent intervals following each dose to assess response and avoid excessive hypotension.
- Route: IV only per source dosing guidance
- Monitoring: Continuous or frequent blood pressure monitoring; heart rate monitoring for reflex tachycardia
- Key adverse effects: Reflex tachycardia, hypotension, headache, flushing
- Renal consult: Required for all non-ICU patients
- Max dose: 20 mg/dose IV — do not exceed
- Consult institutional protocol for concentration, diluent, and infusion rate specifics
Disclaimer: This article is an educational reference summarizing standard pediatric dosing values. It is not a substitute for clinical judgment. Always verify doses against institutional protocols, the current edition of authoritative references (e.g., Lexicomp, Harriet Lane Handbook, PALS guidelines), the patient’s accurate weight, and any patient-specific factors (renal/hepatic function, allergies, comedications) before administration.