Normodyne

Labetalol can mask early warning symptoms of hypoglycemia (low blood sugar) such as tremors and increased heart rate which are the result of activation of the adrenergic nervous system. Therefore, people with diabetes taking medications that lower blood sugar such as insulin or oral antidiabetic medications may need to increase the frequency with which they monitor their blood sugar in order to prevent hypoglycemia.

Combining labetalol with tricyclic antidepressants such as amitriptyline (Elavil, Endep), imipramine (Tofranil), or nortriptyline (Pamelor) may lead to an increase in tremor which is a side effect of tricyclic antidepressants.

If combined with adrenergic stimulating drugs used for treating asthma, for example, albuterol (Proventil, Ventolin) or pirbuterol (Maxair), the adrenergic blocking effects of labetalol may counteract the effects of the stimulating drugs and reduce their effectiveness for treating asthmatic attacks. More of the adrenergic drug may be needed.

Glutethimide (Doriden) may decrease the effectiveness of labetalol by increasing its elimination. When both drugs are used together, more labetalol or less glutethimide may be needed.

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

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

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 breastfeeding
• Are having surgery, including dental surgery

Labetalol and Pregnancy

It's not known whether labetalol will harm an unborn baby, though the drug has been linked to heart and lung problems in newborns.

Labetalol can pass into breast milk and may harm a breastfeeding baby.

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

If you experience any of the following symptoms, call your doctor immediately:

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

Patients who take diabetes medications to lower blood sugar (such as insulin or oral antidiabetic 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.

Combining labetalol with tricyclic antidepressants such as amitriptyline (Elavil, Endep), imipramine (Tofranil), or nortriptyline (Pamelor) may lead to an increase in tremor.

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.

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.

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.

Labetalol Overdose

If you suspect an overdose, you should contact a poison control center or emergency room immediately.

You can get in touch with a poison control center at (800) 222-1222.

Missed Dose of Labetalol

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 is a prescription medication used to treat high blood pressure.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Common side effects include:

• dizziness
• nausea
• tiredness
• headache
• stuffy nose

This is not a complete list of labetalol side effects. Ask your doctor or pharmacist for more information.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Labetalol is used alone or together with other medicines to treat high blood pressure (hypertension). High blood pressure adds to the workload of the heart and arteries. If it continues for a long time, the heart and arteries may not function properly. This can damage the blood vessels of the brain, heart, and kidneys, resulting in a stroke, heart failure, or kidney failure. High blood pressure may also increase the risk of heart attacks. These problems may be less likely to occur if blood pressure is controlled .

This medicine is a beta-blocker. It works by affecting the response to nerve impulses in certain parts of the body, like the heart. As a result, the heart beats slower and decreases the blood pressure. When the blood pressure is lowered, the amount of blood and oxygen is increased to the heart .

This medicine is available only with your doctor's prescription .

This section provides information on the proper use of a number of products that contain labetalol. It may not be specific to Normodyne. Please read with care.

In addition to the use of this medicine, treatment for your high blood pressure may include weight control and changes in the types of foods you eat, especially foods high in sodium. Your doctor will tell you which of these are most important for you. You should check with your doctor before changing your diet .

Many patients who have high blood pressure will not notice any signs of the problem. In fact, many may feel normal. It is very important that you take your medicine exactly as directed and that you keep your appointments with your doctor even if you feel well .

Remember that this medicine will not cure your high blood pressure, but it does help control it. You must continue to take it as directed if you expect to lower your blood pressure and keep it down. You may have to take high blood pressure medicine for the rest of your life. If high blood pressure is not treated, it can cause serious problems such as heart failure, blood vessel disease, stroke, or kidney disease .

Do not interrupt or stop taking this medicine without first checking with your doctor. Your doctor may want you to gradually reduce the amount you are taking before stopping it completely. Some conditions may become worse when the medicine is stopped suddenly, which can be dangerous .

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For oral dosage form (tablets):
  • For high blood pressure:
    • Adults—At first, 100 milligrams (mg) two times a day. Your doctor may increase your dose if needed.
    • Children—Use and dose must be determined by your doctor .

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Applies to labetalol: compounding powder, intravenous solution, oral tablet

Cardiovascular

Common (1% to 10%): Edema, postural hypotension
Frequency not reported: Bradycardia, heart block, heart failure, hypotension, ankle edema, increase of an existing intermittent claudication, postural hypotension, cold or cyanotic extremities, Raynaud's phenomenon, paresthesia of the extremities, syncope[Ref]

Dermatologic

Uncommon (0.1% to 1%): Increased sweating
Frequency not reported: Systemic lupus erythematosus, rashes (e.g., generalized maculopapular, lichenoid, urticarial, bullous lichen planus, psoriaform, facial erythema, Peyronie's disease, reversible alopecia)[Ref]

Endocrine

Frequency not reported: Masking of the normal response to hypoglycemia (sweating and tachycardia); this may be important in some patients with diabetes mellitus[Ref]

Gastrointestinal

Common (1% to 10%): Nausea, dyspepsia, vomiting
Uncommon (0.1% to 1%): Diarrhea
Frequency not reported: Epigastric pain[Ref]

Genitourinary

Common (1% to 10%): Ejaculation failure, impotence
Frequency not reported: Difficulty in micturition (including acute urinary bladder retention)[Ref]

Hepatic

Common (1% to 10%): Transient elevations of liver function tests
Frequency not reported: Hepatic necrosis, hepatitis, cholestatic jaundice[Ref]

Hypersensitivity

Rare (less than 0.1%): Hypersensitivity (e.g., rash, urticaria, pruritus, angioedema, dyspnea), anaphylactoid reactions[Ref]

Immunologic

Frequency not reported: Antimitochondrial antibodies[Ref]

Metabolic

Very rare (less than 0.01%): Hyperkalemia[Ref]

Musculoskeletal

Frequency not reported: Muscle cramps, toxic myopathy[Ref]

Nervous system

Very common (10% or more): Dizziness (11%)
Common (1% to 10%): Headache, taste distortion, vertigo, paresthesia, scalp tingling
Uncommon (0.1% to 1%): Drowsiness
Frequency not reported: Tremor[Ref]

Ocular

Common (1% to 10%): Vision abnormality
Frequency not reported: Dry eyes
Postmarketing reports: Intraoperative Floppy Iris Syndrome (IFIS) observed during cataract surgery[Ref]

Respiratory

Common (1% to 10%): Nasal stuffiness, dyspnea
Frequency not reported: Bronchospasm, interstitial lung disease[Ref]

Other

Common (1% to 10%): Fatigue, asthenia
Frequency not reported: Positive antinuclear factor[Ref]

Psychiatric

Frequency not reported: Depressed mood and lethargy, hallucinations, psychoses, confusion, sleep disturbances, nightmares[Ref]

Some side effects of Normodyne may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.