How do you prescribe Labetalol (Labetalol) intravenously for resistant Hypertension (HTA)?

From the Guidelines

Labetalol IV should be administered for resistant hypertension starting with a 0.3–1.0-mg/kg dose (maximum 20 mg) slow IV injection every 10 min or 0.4–1.0-mg/kg/h IV infusion up to 3 mg/kg/h, with a total cumulative dose of 300 mg, as recommended by the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline 1. The initial dose can be repeated every 10 minutes, and the infusion rate can be adjusted to achieve the target blood pressure.

• Key considerations for labetalol administration include:
  • Contraindications: reactive airways disease, chronic obstructive pulmonary disease, second- or third-degree heart block, bradycardia, and heart failure 1
  • Monitoring: blood pressure and heart rate should be continuously monitored, with the patient in a supine position to prevent orthostatic hypotension
  • Mechanism of action: dual alpha-1 and beta-adrenergic receptor blockade, providing rapid blood pressure reduction with less reflex tachycardia than pure vasodilators
  • Potential adverse effects: hypotension, bradycardia, and bronchospasm, which should be managed promptly with resuscitation equipment available during administration It is essential to note that labetalol is especially useful in hyperadrenergic syndromes, but its use requires caution in patients with certain comorbidities, as outlined in the guidelines 1.

From the FDA Drug Label

DOSAGE AND ADMINISTRATION Labetalol HCl Injection is intended for intravenous use in hospitalized patients. DOSAGE MUST BE INDIVIDUALIZED depending upon the severity of hypertension and the response of the patient during dosing. Either of two methods of administration of labetalol HCl injection may be used: a) repeated intravenous injections, b) slow continuous infusion Repeated Intravenous Injection Initially, labetalol HCl injection should be given in a dose of 20 mg labetalol HCl (which corresponds to 0. 25 mg/kg for an 80 kg patient) by slow intravenous injection over a 2-minute period. Additional injections of 40 mg or 80 mg can be given at 10-minute intervals until a desired supine blood pressure is achieved or a total of 300 mg labetalol HCl has been injected Slow Continuous Infusion Labetalol HCl Injection is prepared for continuous intravenous infusion by diluting the vial contents with commonly used intravenous fluids The diluted solution should be administered at a rate of 2 mL/min to deliver 2 mg/min The rate of infusion of the diluted solution may be adjusted according to the blood pressure response, at the discretion of the physician.

To prescribe Labetalol (Labetalol) intravenously for resistant Hypertension (HTA), the following steps can be taken:

• Initial Dose: Administer 20 mg of labetalol HCl by slow intravenous injection over a 2-minute period.
• Repeated Intravenous Injections: Give additional injections of 40 mg or 80 mg at 10-minute intervals until a desired supine blood pressure is achieved or a total of 300 mg labetalol HCl has been injected.
• Slow Continuous Infusion: Prepare the infusion solution by diluting the vial contents with commonly used intravenous fluids and administer at a rate of 2 mL/min to deliver 2 mg/min.
• Adjust Infusion Rate: Adjust the rate of infusion according to the blood pressure response, at the discretion of the physician. 2

From the Research

Resistant Hypertension Treatment

The provided studies do not specifically address the intravenous prescription of Labetalol for resistant hypertension. However, they do discuss the general management of resistant hypertension:

• Resistant hypertension is defined as blood pressure that remains above goal despite the use of at least three antihypertensive agents of different classes, one of which is a diuretic 3, 4, 5, 6, 7.
• The management of resistant hypertension typically involves lifestyle modifications, such as exercise and dietary sodium restriction, as well as the use of multiple antihypertensive agents 3, 4, 5, 6, 7.
• The use of a diuretic, a dihydropyridine calcium channel blocker, and an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker is often recommended 3, 4, 5, 7.
• Other options for the treatment of resistant hypertension include the use of a beta blocker, a long-acting nondihydropyridine calcium channel blocker, or clonidine or guanfacine 3, as well as the use of an aldosterone antagonist as a fourth-line therapy 5, 7.

Labetalol Use

There is no specific information provided in the studies about the intravenous use of Labetalol for resistant hypertension. Labetalol is mentioned as a potential option for the treatment of resistant hypertension, but only as a beta blocker in general 3.

Key Points

• Resistant hypertension requires a comprehensive approach to management, including lifestyle modifications and the use of multiple antihypertensive agents.
• The specific use of Labetalol intravenously for resistant hypertension is not addressed in the provided studies.
• Further research or consultation with a hypertension specialist may be necessary to determine the best course of treatment for individual patients with resistant hypertension.