From the FDA Drug Label
Labetalol HCl's beta1-receptor blockade in man was demonstrated by a small decrease in the resting heart rate, attenuation of tachycardia produced by isoproterenol or exercise, and by attenuation of the reflex tachycardia to the hypotension produced by amyl nitrite. Labetalol HCl consistently, in dose-related fashion, blunted increases in exercise-induced blood pressure and heart rate, and in their double product. Labetalol HCl produces dose-related falls in blood pressure without reflex tachycardia and without significant reduction in heart rate, presumably through a mixture of its alpha- and beta-blocking effects.
Labetalol's effect on heart rate:
- Labetalol can cause a small decrease in resting heart rate due to its beta1-receptor blockade.
- It attenuates tachycardia produced by isoproterenol, exercise, or reflex tachycardia.
- However, labetalol does not significantly reduce heart rate at rest, as it produces dose-related falls in blood pressure without reflex tachycardia.
From the Research
Yes, labetalol can bring down heart rate. Labetalol is a medication that works as both an alpha and beta blocker, meaning it blocks certain receptors in the body that respond to adrenaline. The beta-blocking effect specifically slows down heart rate and reduces the force of heart contractions. Labetalol is commonly used to treat high blood pressure and can be administered orally or intravenously in emergency situations. Typical oral doses range from 100-400 mg twice daily, with a maximum daily dose of 2400 mg. When given intravenously, it's usually administered in smaller, incremental doses under close medical supervision. The heart rate reduction typically begins within 5 minutes of IV administration or within 1-2 hours of oral dosing. Patients should be aware that labetalol may cause dizziness, especially when standing up quickly, and should monitor their blood pressure and heart rate regularly. This medication should not be stopped suddenly as this can lead to rebound high blood pressure or increased heart rate, as noted in studies such as 2.
Some key points to consider when using labetalol include:
- It is effective in reducing blood pressure and heart rate in patients with hypertension, including those with renal hypertension or hypertensive emergencies 3.
- Labetalol has a favorable hemodynamic profile, reducing peripheral and coronary vascular resistances while preserving cardiac output 2.
- The medication can cause side effects such as dizziness, gastrointestinal disturbances, and tiredness, but these are generally manageable with proper dosing and monitoring 4.
- Labetalol may be particularly useful in certain patient populations, such as Black patients, the elderly, and those with renal hypertension, due to its effectiveness and tolerability in these groups 3.
Overall, labetalol is a valuable medication for managing high blood pressure and reducing heart rate, with a range of benefits and potential uses in different patient populations, as supported by studies such as 5 and 6.