Labetalol

Labetalol is a drug used to treat high blood pressure. It belongs to a class of medications known as beta blockers. This drug is not a cure for high blood pressure, but it can help reduce systolic and diastolic blood pressure. It comes in tablet form and is available in several different strengths. Common side effects include nausea, heartburn, and fatigue.

What Is Labetalol?

Labetalol hydrochloride (Trandate®) is a prescription medicine that has been licensed for controlling high blood pressure (hypertension) in adults. However, it is not a cure for high blood pressure.
 
The medication has not been approved for use in children.
 
(Click What Is Labetalol Used For? for more information, including possible off-label uses.)
 

Possible Side Effects

As with any medicine, side effects can occur with labetalol.
 However, not everyone who takes it will experience problems. In fact, most people tolerate the medicine well. If side effects do occur, they are often minor and either require no treatment or can easily be treated by you or your healthcare provider. Serious side effects are less common.
 
The most common side effects include:
 
  • Nausea
  • Dizziness
  • Fatigue
  • Nasal stuffiness
  • A slow heart rate.
     
(Click Labetalol Side Effects to learn more, including potentially serious side effects you should report to your healthcare provider.)
 
You can also read about other possible side effects in the following eMedTV links:
 
 

What Should I Tell My Healthcare Provider?

Before taking labetalol, let your healthcare provider know if you have:
 
 
 
Also, let your healthcare provider know if you:
 
Tell your healthcare provider about all other medicines you are currently taking, including prescription and nonprescription medicines, vitamins, and herbal supplements.
 
(Click Precautions and Warnings With Labetalol to learn more, including information on who should not take the drug.)
 

How Does This Medication Work?

Labetalol is part of a class of drugs called beta-adrenergic blocking agents, or beta blockers for short. As the name implies, beta blockers block beta receptors in the body. Beta receptors are located in a number of places, including the heart and blood vessels. These receptors are what stress hormones such as adrenaline attach to and cause certain reactions in the body, such as an increase in:
 
By blocking beta receptors, labetalol causes the reverse effect of stress hormones. It decreases heart rate and both systolic and diastolic blood pressure, as well as the workload of the heart.
 
Unlike a lot of other beta blockers, this medication also blocks alpha receptors. The alpha blocker component works more on the peripheral blood vessels (arteries and veins in the arms and legs). By blocking the alpha receptors, labetalol causes these blood vessels to relax.
 

Effects of Labetalol

A blood pressure reading consists of two numbers -- for example, 120/80. The top number is the systolic blood pressure, and the bottom number is the diastolic blood pressure. During clinical studies in people taking labetalol, both systolic and diastolic blood pressure decreased significantly. The higher the dose, the greater the drop in blood pressure tended to be.
 
By lowering blood pressure, labetalol can decrease the risk of developing health problems, such as a heart attack or stroke, that can result from long-term hypertension (see Effects of High Blood Pressure).
 

When and How Do I Take It?

Some general considerations for when and how to take labetalol include the following:
 
  • The medication comes in tablet form. It is also available in injection form for use in the hospital setting. Generally, people take it two or three times a day.
     
  • You may take your dose with or without food.
     
  • Take your labetalol dosage at the same time each day to maintain an even level in your blood.
     
  • For labetalol to work properly, you have to take it as prescribed. The medication will not work if you stop taking it.
     
  • You should not stop taking labetalol without first discussing it with your healthcare provider. Stopping the drug abruptly increases the risk for serious side effects (see Precautions and Warnings With Labetalol).
     

Dosing Information

The dose of labetalol your healthcare provider recommends will vary, depending on a number of factors, including:
 
  • Other medical conditions you may have
  • Other medications you may be taking
  • How you respond to the drug.
     
As is always the case, do not adjust your dose unless your healthcare provider specifically instructs you to do so.
 
(Click Labetalol Dosing for more information.)
  

Drug Interactions

Labetalol may interact with a number of different medications (see Drug Interactions With Labetalol for more information).
  

What If I Take an Overdose?

People who take too much labetalol may have overdose symptoms that could include but are not limited to:
 
 
If you happen to take too much, seek immediate medical attention.
 
(Click Labetalol Overdose for more information.)
 

How Should Labetalol Be Stored?

Store labetalol at room temperature in a dry place, away from moisture and heat. Keep the tablets in an airtight, light-resistant container.
 
Keep this and all medications out of the reach of children.
 

What Should I Do If I Miss a Dose?

If you do not take your labetalol as scheduled, take the missed dose as soon as you remember. If it is almost time for your next scheduled dose, skip the missed one and continue with normal dosing. Never take a double dose.
 

Who Makes This Medicine?

Labetalol is manufactured by Prometheus Laboratories. A number of companies manufacture generic versions, such as Watson Pharmaceuticals, Teva Pharmaceuticals, and Eon Laboratories.
  

Available Strengths

Labetalol tablets come in a number of strengths, including:
 
  • Labetalol 100 mg
  • Labetalol 200 mg
  • Labetalol 300 mg.
 
An injectable form is also available.
 

Generic Labetalol

Labetalol is currently available as a generic medicine (see Generic Labetalol for more information).
 
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD
Last reviewed by: Kristi Monson, PharmD;
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