Intravenous Labetalol Administration for Acute Hypertension
For acute hypertension, labetalol 10 mg IV can be repeated every 10-20 minutes, with a maximum total dose of 300 mg. 1
Dosing Guidelines Based on Clinical Scenario
For Patients Eligible for Thrombolytic Therapy (Pre-treatment)
- Initial dose: Labetalol 10-20 mg IV over 1-2 minutes 1
- May repeat once if blood pressure remains >185/110 mmHg 1
- If blood pressure is not reduced to <185/110 mmHg, do not administer rtPA 1
During and After Thrombolytic Treatment
For systolic BP 180-230 mmHg or diastolic BP 105-120 mmHg:
For systolic BP >230 mmHg or diastolic BP 121-140 mmHg:
For Patients Not Eligible for Thrombolytic Therapy
- For systolic BP >220 mmHg or diastolic BP 121-140 mmHg:
Monitoring Requirements
- For patients receiving thrombolytic therapy:
Important Considerations
Safety Precautions
- Avoid rapid and steep reductions in blood pressure as this may cause neurological worsening 1
- Target a gradual 15-25% reduction in blood pressure within the first day 1
- Bolus injections may be less efficient and cause more side effects than incremental infusion 3
- Be vigilant for potential hypotension, especially with repeated doses 4
Contraindications
- Second or third-degree heart block 2
- Bradycardia 2
- Decompensated heart failure 2
- Asthma (relative contraindication due to beta-blocking effects) 1, 5
Efficacy Considerations
- Labetalol is particularly effective in hyperadrenergic states 2
- Patients with higher baseline plasma noradrenaline levels may show greater response to labetalol 6
- Labetalol produces a decrease in peripheral vascular resistance without significant alteration in heart rate or cardiac output 7, 5