Maximum Dose of Oral Labetalol
The maximum daily dose of oral labetalol is 2400 mg per day, typically administered as 1200 mg twice daily. 1
Standard Dosing Parameters
- Starting dose: 200 mg twice daily 1
- Maximum daily dose: 2400 mg total 1, 2
- Typical maintenance range: 200-800 mg daily in divided doses 2
- Dosing frequency: Usually administered twice daily (BID), though may require three or four times daily dosing in pregnancy due to accelerated drug metabolism 2
Titration Approach
- Titration interval: Increase dose every 2-3 days in stable patients 1
- Dose escalation: Can be increased from the starting dose of 200 mg BID up to the maximum of 1200 mg BID based on blood pressure response 1, 2
Special Clinical Contexts
Hypertensive Urgencies (Oral Administration)
For acute management in the emergency department setting:
- Initial oral dose: 300 mg as a single dose 3
- Subsequent dosing: 100 mg every 2 hours if diastolic BP remains >100 mmHg 3
- Maximum acute dose: 500 mg total in the emergency setting 3
- Alternative dosing: Single doses of 100-300 mg have proven safe and effective, with response rates of 50-75% at 2-4 hours 4
Pregnancy and Postpartum
- Pregnancy considerations: Labetalol is a first-line agent but may require more frequent dosing (3-4 times daily) due to accelerated metabolism 2
- Postpartum limitation: May be less effective than calcium channel blockers in the postpartum period and associated with higher readmission risk 2
Critical Contraindications
Avoid labetalol in patients with: 1, 2
- Bradycardia or second/third-degree heart block
- Bronchospasm, asthma, or COPD
- Decompensated heart failure
- Severe sinus node dysfunction
Important Clinical Pearls
- Combination therapy: Often used with hydrochlorothiazide 25-50 mg daily for enhanced efficacy 1, 5
- Withdrawal risk: Can cause rebound hypertension if discontinued abruptly 1
- Side effect profile: Common adverse effects include peripheral edema, postural hypotension, scalp tingling, and fluid retention (easily managed with diuretics) 1, 6
- Monitoring: Watch for volume status changes to minimize risk of placental hypoperfusion in pregnancy 1
The 2400 mg daily maximum is well-established across multiple guidelines, though most patients achieve adequate control with doses below 800 mg daily. 1, 2