Labetalol Dosage for Essential Hypertension
The recommended initial dosage of labetalol for essential hypertension is 100 mg twice daily, with titration in increments of 100 mg twice daily every 2-3 days to a usual maintenance dosage between 200-400 mg twice daily. 1
Initial Dosing and Titration
- Starting dose: 100 mg twice daily (whether used alone or added to a diuretic regimen) 1
- Titration schedule: Increase by 100 mg twice daily every 2-3 days based on standing blood pressure response 1
- Usual maintenance dose: 200-400 mg twice daily 1
- Maximum daily dose: 1,200-2,400 mg for severe hypertension, with or without thiazide diuretics 1
Dosing Considerations
Combination Therapy
- When adding labetalol to hydrochlorothiazide, significant blood pressure reductions can be achieved compared to diuretic alone 2, 3
- The median effective dose when combined with hydrochlorothiazide is 400 mg twice daily 2
- When a diuretic is added to labetalol therapy, an additive antihypertensive effect occurs, which may necessitate labetalol dosage adjustment 1
Special Populations
- Elderly patients: Start with 100 mg twice daily and titrate as needed, but lower maintenance dosages (100-200 mg twice daily) are often effective due to slower elimination 1
- Patients with side effects: If side effects (primarily nausea or dizziness) occur with twice-daily dosing, the same total daily dose administered three times daily may improve tolerability 1
Administration Pearls
- Full antihypertensive effect is usually seen within 1-3 hours of initial dose or dose increment 1
- Titration increments should not exceed 200 mg twice daily 1
- When transferring from other antihypertensive drugs, introduce labetalol as recommended and progressively decrease the dosage of existing therapy 1
Monitoring
- Assess blood pressure response approximately 12 hours after a dose to determine if further titration is necessary 1
- Monitor for common side effects including dizziness, fatigue, nausea, rash, and pruritus 2
Alternative Formulations
For hypertensive emergencies requiring intravenous administration:
- Initial IV dose: 0.25-0.5 mg/kg or 10-20 mg IV 4
- Maintenance infusion: 2-8 mg/min or 5-20 mg/hour 4
- Maximum cumulative IV dose: 300 mg 4
Contraindications
Labetalol is contraindicated in patients with:
- Reactive airway disease
- Second or third-degree AV block
- Severe bradycardia
- Heart failure 4
By following this dosing regimen, labetalol provides effective blood pressure control for patients with essential hypertension while minimizing adverse effects.