Levoxyl

Generic Name: levothyroxine (LEE voe thye ROX een)
Brand names: Levothroid, Levoxyl, Synthroid, Tirosint, Unithroid

What is Levoxyl?

Levoxyl (levothyroxine) is a replacement for a hormone that is normally produced by your thyroid gland to regulate the body's energy and metabolism. Levoxyl is given when the thyroid does not produce enough of this hormone on its own.

Levoxyl treats hypothyroidism (low thyroid hormone). It is also used to treat or prevent goiter (enlarged thyroid gland), which can be caused by hormone imbalances, radiation treatment, surgery, or cancer.

Levoxyl should not be used to treat obesity or weight problems.

Levoxyl may also be used for purposes not listed in this medication guide.

Important information about Levoxyl

Since thyroid hormone occurs naturally in the body, almost anyone can take Levoxyl. You should not use Levoxyl if you have had a heart attack, a thyroid disorder called thyrotoxicosis, or an adrenal gland problem that is not controlled by treatment.

Before you take Levoxyl, tell your doctor if you have a serious thyroid disorder (thyrotoxicosis), heart disease, coronary artery disease, diabetes, anemia, problems with your pituitary or adrenal glands, a history of blood clots, if you have recently had a heart attack, or if you are having any symptoms of a heart attack (chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling).

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If you use insulin or take diabetes medicine by mouth, ask your doctor if your dose needs to be changed when you start using Levoxyl.

Different brands of levothyroxine may not work the same. If you get a prescription refill and your new pills look different, talk with your pharmacist or doctor.

It may take several weeks before your body starts to respond to Levoxyl. Do not stop taking the medicine suddenly, even if you feel well.

Many other medicines can be affected by your thyroid hormone levels. Other medicine may also increase or decrease the effects of levothyroxine.

Tell your doctor about all medications you use, start using, or stop using during your treatment with Levoxyl. This includes prescription, over-the-counter, vitamin, and herbal products. Keep a list of all your medicines and show it to any healthcare provider who treats you.

Before taking Levoxyl

Since thyroid hormone occurs naturally in the body, almost anyone can take Levoxyl. However, you may not be able to take this medication if you have certain medical conditions.

Tell your doctor if you have recently received radiation therapy with iodine (such as I-131).

To make sure you can safely take Levoxyl, tell your doctor if you have:

• a thyroid disorder called thyrotoxicosis;

• heart disease, coronary artery disease, or a history of blood clots;

• diabetes;

• anemia (lack of red blood cells);

• problems with your pituitary or adrenal glands;

• an untreated or uncontrolled adrenal gland disorder; or

• if you have recently had a heart attack, or are having any symptoms of a heart attack (chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling).

If you use insulin or take diabetes medicine by mouth, ask your doctor if your dose needs to be changed when you start using Levoxyl.

In most cases, you will need to take levothyroxine for the rest of your life. Taking levothyroxine over long periods of time may cause bone loss, which can lead to osteoporosis. Talk with your doctor about how this could affect you.

FDA pregnancy category A. Levoxyl is not expected to harm an unborn baby. If you become pregnant while taking Levoxyl, do not stop taking the medicine without your doctor's advice. Having low thyroid hormone levels during pregnancy could harm both mother and baby. Your dose needs may be different during pregnancy. Levothyroxine can pass into breast milk, but it is not expected to be harmful to a nursing baby. Do not use Levoxyl without telling your doctor if you are breast-feeding a baby. Your dose needs may be different while you are nursing.

See also: Levoxyl pregnancy and breastfeeding warnings (in more detail)

How should I take Levoxyl?

Take Levoxyl exactly as prescribed by your doctor. Follow the directions on your prescription label.

Do not take this medicine in larger or smaller amounts or for longer than recommended. Your doctor may occasionally change your dose to make sure you get the best results.

It is very important to take Levoxyl with a full glass (8 ounces) of water. The Levoxyl tablet can dissolve very quickly and swell in the throat, possibly causing choking or gagging. Take Levoxyl on an empty stomach, 30 minutes before eating. Levoxyl is usually taken in the morning. Follow your doctor's dosing instructions and try to take the medicine at the same time each day. It may take several weeks before your body starts to respond to this medication. Do not stop taking this medication suddenly. Even if you feel well, you may still need to take Levoxyl every day for the rest of your life to replace the thyroid hormone your body cannot produce.

While using Levoxyl, you may need frequent medical tests at your doctor's office.

Tell any doctor or dentist who treats you that you are using Levoxyl.

Store Levoxyl at room temperature away from moisture and heat.

See also: Levoxyl dosage (in more detail)

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include chest pain, pounding heartbeats, tremors, shortness of breath, leg cramps, confusion, vomiting, diarrhea, or seizures.

What should I avoid while taking Levoxyl?

Certain medicines can make Levoxyl less effective if taken at the same time. If you use any of the following drugs, avoid taking them within 4 hours before or 4 hours after you take Levoxyl:

• calcium carbonate (Caltrate, Citracal, Oystercal, and others);

• ferrous sulfate iron supplement;

• sucralfate (Carafate);

• sodium polystyrene sulfonate (Kayexalate, Kionex, and others);

• antacids that contain aluminum or magnesium (such as Acid Gone, Aldroxicon, Alternagel, Di-Gel, Gaviscon, Gelusil, Genaton, Maalox, Maldroxal, Milk of Magnesia, Mintox, Mylagen, Mylanta, Pepcid Complete, Rolaids, Rulox); or

• cholesterol-lowering drugs cholestyramine (Questran) and colestipol (Colestid).

Do not change brands or change to a generic levothyroxine drug product without first asking your doctor. Different brands of levothyroxine may not work the same. If you get a prescription refill and your new pills look different, talk with your pharmacist or doctor.

Avoid the following food products, which can make your body absorb less levothyroxine: infant soy formula, cotton seed meal, walnuts, and high-fiber foods.

Levoxyl side effects

Get emergency medical help if you have any of these signs of an allergic reaction to Levoxyl: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have a serious side effect such as:

• headache;

• sleep problems (insomnia);

• feeling nervous or irritable;

• fever, hot flashes, sweating;

• pounding heartbeats or fluttering in your chest;

• changes in your menstrual periods; or

• appetite changes, weight changes.

Less serious Levoxyl side effects may include mild hair loss.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Levoxyl side effects (in more detail)

What other drugs will affect Levoxyl?

Many other medicines can be affected by your thyroid hormone levels. Other medicine may also increase or decrease the effects of levothyroxine.

Many drugs can interact with levothyroxine and not all possible interactions are listed in this medication guide.

Tell your doctor about all medications you use, start using, or stop using during your treatment with Levoxyl. This includes prescription, over-the-counter, vitamin, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.

Where can I get more information?

• Your pharmacist can provide more information about Levoxyl.