What Is Labetalol?

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Labetalol is a drug used to treat high blood pressure. It's also known by its brand names Normodyne and Trandate.

This medicine is in a group of drugs called beta-blockers. It works by relaxing blood vessels and slowing heart rate to improve blood flow and decrease blood pressure.

Labetalol is also sometimes used to treat chest pain and to treat people with tetanus.

The drug comes in a tablet and intravenous (IV) form. Labetalol controls high blood pressure, but it does not cure it. You should continue to take labetalol even if you feel well. The drug is only part of a complete treatment program for high blood pressure that may also include diet, exercise, and weight control.

The Food and Drug Administration approved labetalol in 1984; the drug is manufactured by Prometheus Laboratories.

Labetalol Warnings

You should not stop taking labetalol without talking to your doctor first. If this drug is stopped suddenly, it may cause chest pain or heart attack in some people.

This medication may also make you drowsy, so you should not drive a car or operate machinery until you know how it will affect you.

Your blood pressure should be checked regularly to evaluate your response to labetalol. You should also check your pulse periodically. If your pulse rate is faster or slower than it should be, call your doctor.

Before taking labetalol, you should tell your doctor and pharmacist if you:

  • Are allergic to it or another other drugs
  • Have ever had heart, kidney, or liver disease; asthma or other lung disease; severe allergies; diabetes, or pheochromocytoma (an adrenal gland tumor)
  • Are pregnant, plan to become pregnant, or are breast-feeding
  • Are having surgery, including dental surgery

It is not known whether labetalol will harm an unborn baby. The drug may cause heart or lung problems in newborns if the mother takes it during pregnancy. Labetalol can pass into breast milk and may harm a nursing baby.

Labetalol Side Effects

Common Side Effects of Labetalol

Some side effects of labetalol may include:

  • Excessive tiredness
  • Tingling scalp or skin
  • Dizziness
  • Lightheadedness
  • Upset stomach
  • Stuffy nose
  • Fatigue

Serious Side Effects of Labetalol


  • Swelling of the lower legs and feet
  • Sudden weight change
  • Shortness of breath or wheezing
  • Chest pain
  • Severe slow heart rate

Labetalol Interactions

In This Section:

Do Other Drugs Affect the Way Labetalol Works?

Patients who take diabetes medications to lower blood sugar (such as insulin or oral anti-diabetic drugs) may need to monitor their blood sugar more frequently while taking labetalol.

Halothane anesthesia may contribute to the blood-pressure lowering effects of labetalol.


If combined with adrenergic-stimulating drugs used for treating asthma, such as albuterol (Proventil, Ventolin) or pirbuterol (Maxair), the effects of labetalol may counteract the effects of the stimulating drugs and reduce their effectiveness.

Cimetidine (Tagamet) may increase the effectiveness of labetalol by blocking its elimination and increasing its levels in the blood. Less labetalol may be needed when cimetidine and labetalol are used together.

You should tell your doctor about all prescription, non-prescription, illegal, recreational, herbal, nutritional, or dietary drugs or supplements you are taking.

Should I Avoid Any Food, Drink or Activity While Taking Labetalol?

You can continue your normal diet and activities unless otherwise instructed by your doctor while taking labetalol. However, consuming alcohol while on labetalol can make you drowsier.

Labetalol Dosage

In This Section:

What Are the Typical Dosages for Labetalol?

The recommended starting oral dose of labetalol is 100 milligrams (mg), twice a day. The dose can be increased by 100 mg twice daily, every two to three days based on your response. Usual maintenance doses are 200-400 mg, twice daily. People with very high blood pressure may require 1.2 to 2.4 grams daily.

The initial intravenous dose of the drug is 20 mg injected over two minutes. Additional injections of 40 or 80 mg may be given every 10 minutes as needed up to a total dose of 300 mg. The medicine may also be given by intravenous infusion at 1 to 2 milligrams/minute.

What Happens if I Take too Much Labetalol and Overdose?


What Happens if I Miss a Dose of Labetalol or Don't Take It as Prescribed?

If you miss a dose of labetalol, take it as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and continue to follow your regular dosing schedule. Do not double up on doses.

Labetalol Pictures

Labetalol 300 mg-IVA, green, round,
Labetalol 100 mg-IVA, yellow, round,
Labetalol 200 mg-IVA, white, round,
Labetalol 300 mg-IVA, green, round, film coated
Labetalol 100 mg-EON, white, round,
Labetalol 200 mg-EON, white, round,
Labetalol 300 mg-EON, white, round,
Labetalol 100 mg-WAT, beige, round, film coated
Labetalol 200 mg-WAT, white, round, film coated
Labetalol 300 mg-WAT, blue, round, film coated

Labetalol FAQ

Q: Can labetalol tablets (200 mg) cause nipple tenderness in the breasts?

A: In looking through articles and drug information books, I found that beta blockers, the family of medications that labetolol belongs to, can rarely cause breast enlargement or milk production in female patients. This is a far stretch from nipple tenderness, but since the medication could possibly cause breast issues, it could be an extremely rare cause of your problem. You should consult your physician about this issue to see if there are any other factors contributing to the tenderness.

Q: Does labetalol have any long-term side effects, or can it damage my body in any way in the long run?

A: The most common adverse effects occurring in greater than 10 percent of patients in clinical studies associated with labetalol (Trandate) include: postural hypotension (drop in blood pressure due to changes in body position), dizziness, fatigue, and nausea. There are other side effects associated with labetalol that are less common. There have been rare reported issues with liver injury while taking labetalol. It is recommended that liver function tests be done periodically when taking the medication for a prolonged period. There is little information about specific long-term side effects with the medication in research articles. Please talk with your health care provider regarding questions you have about your medications. Jen Marsico, RPh