What is the maximum dose of Labetalol (labetalol) for treating tachycardia and hypertension?

From the Guidelines

The maximum dose of labetalol for treating tachycardia and hypertension is 300 mg, typically given as repeated boluses of 10-20 mg every 10 minutes or as a continuous infusion at 0.4-1.0-mg/kg/h IV infusion up to 3 mg/kg/h, with a total cumulative dose of 300 mg. This recommendation is based on the most recent and highest quality study available, which prioritizes the safety and efficacy of labetalol in managing hypertensive emergencies 1.

Key Considerations

• Labetalol works by blocking both alpha and beta adrenergic receptors, providing simultaneous reduction in peripheral vascular resistance and heart rate.
• Monitor blood pressure and heart rate closely during administration.
• Be cautious in patients with asthma, COPD, heart failure, or diabetes as beta-blockers can exacerbate these conditions.
• Abrupt discontinuation should be avoided to prevent rebound hypertension.

Administration Guidelines

• Initial dose: 0.3–1.0-mg/kg dose (maximum 20 mg) slow IV injection every 10 min.
• Infusion rate: 0.4–1.0-mg/kg/h IV infusion up to 3 mg/kg/h.
• Total cumulative dose: 300 mg.
• Repeat dose: every 4–6 h as needed to lower BP to target.

Important Notes

• Contraindicated in reactive airways disease or chronic obstructive pulmonary disease.
• Especially useful in hyperadrenergic syndromes.
• May worsen HF and should not be given in patients with second- or third-degree heart block or bradycardia.

From the FDA Drug Label

In a clinical pharmacologic study in severe hypertensives, an initial 0. 25 mg/kg injection of labetalol HCl, administered to patients in the supine position, decreased blood pressure by an average of 11/7 mmHg. Additional injections of 0.5 mg/kg at 15-minute intervals up to a total cumulative dose of 1.75 mg/kg of labetalol HCl caused further dose-related decreases in blood pressure. Some patients required cumulative doses of up to 3. 25 mg/kg. Labetalol HCl administered as a continuous intravenous infusion, with a mean dose of 136 mg (27 to 300 mg) over a period of 2 to 3 hours (mean of 2 hours and 39 minutes) lowered the blood pressure by an average of 60/35 mmHg High-Dose Labetalol HCl Administration of up to 3 g per day as an infusion for up to 2 to 3 days has been anecdotally reported; several patients experienced hypotension or bradycardia

The maximum dose of labetalol for tachycardia and hypertension is:

• Up to 3.25 mg/kg cumulative dose for intravenous injections
• Up to 300 mg cumulative dose for intravenous injections (equivalent to 0.25 mg/kg for an 80 kg patient, with additional doses of 40 or 80 mg at 10-minute intervals)
• Up to 3 g per day as an infusion for up to 2 to 3 days (anecdotally reported) 2, 2

Key considerations:

• The dose should be titrated to achieve the desired effect, with careful monitoring of the patient's blood pressure and heart rate.
• The patient's ability to tolerate an upright position should be established before permitting any ambulation.
• High-dose labetalol administration may cause hypotension or bradycardia.

From the Research

Maximum Dose of Labetalol for Tachycardia and Hypertension

• The maximum dose of labetalol for tachycardia and hypertension is not explicitly stated in the provided studies, but a study published in 2019 3 assessed the safety of high-dose intravenous labetalol in adults and found that the mean dose of labetalol was 996 mg (range 300 to 4465 mg) without significant adverse safety outcomes.
• Labetalol is often used to treat hypertensive emergencies and urgencies, and its efficacy and safety have been compared to other antihypertensive agents such as nicardipine in several studies 4, 5.
• A systematic review published in 2012 4 found that nicardipine and labetalol have comparable efficacy and safety in treating hypertensive crises, although nicardipine may provide more predictable and consistent blood pressure control.
• Another study published in 2021 5 found that continuous infusion of labetalol and nicardipine have similar safety and efficacy in controlling blood pressure in patients with acute stroke, with labetalol having a shorter time to goal blood pressure.
• The use of labetalol in treating tachycardia and hypertension is supported by its ability to control both supraventricular tachyarrhythmias and severe hypertension, as mentioned in a study published in 1995 6.
• However, the study published in 2008 7 notes that labetalol is a rapid-acting intravenous antihypertensive agent that can be used to treat hypertensive emergencies, but its use should be cautious and monitored closely to avoid adverse effects.