Levothyroxine

Levothyroxine, a thyroid hormone, is used to treat hypothyroidism, a condition where the thyroid gland does not produce enough thyroid hormone. Without this hormone, the body cannot function properly, resulting in: poor growth; slow speech; lack of energy; weight gain; hair loss; dry, thick skin; and increased sensitivity to cold. When taken correctly, levothyroxine reverses these symptoms. Levothyroxine is also used to treat congenital hypothyroidism (cretinism) and goiter (enlarged thyroid gland). This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Levothyroxine comes as a tablet to take by mouth. It usually is taken once a day on an empty stomach, one half to one hour before breakfast. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take levothyroxine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. The tablets may get stuck in your throat or cause choking or gagging; therefore, the tablet should be taken with a full glass of water. If you are giving levothyroxine to an infant or child who cannot swallow the tablet, crush the tablet and mix it in 1 to 2 teaspoons of plain water. Give this mixture by spoon or dropper right away. Do not store this mixture. Only mix the crushed tablets with water. Do not mix with food or soybean infant formula. Your doctor will probably start you on a low dose of levothyroxine and gradually increase your dose. Levothyroxine controls hypothyroidism, but does not cure it. It may take several weeks before you notice a change in your symptoms. Continue to take levothyroxine even if you feel well. Do not stop taking levothyroxine without talking to your doctor.

<p></p> <p></p> <p></p> <p>Levothyroxine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

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weight loss</li>
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tremor</li>
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headache</li>
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nausea</li>
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vomiting</li>
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diarrhea</li>
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stomach cramps</li>
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nervousness</li>
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irritability</li>
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insomnia</li>
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excessive sweating</li>
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increased appetite</li>
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fever</li>
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changes in menstrual cycle</li>
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sensitivity to heat</li>
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temporary hair loss, particularly in children during the first month of therapy</li></ul></p> <p></p> <p>If you experience either of the following symptoms, call your doctor immediately:

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chest pain (angina)</li>
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rapid or irregular heartbeat or pulse</li></ul>If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online [at <a href='http://www.fda.gov/Safety/MedWatch'>http://www.fda.gov/Safety/MedWatch</a>] or by phone [1-800-332-1088].</p>

Before taking levothyroxine, tell your doctor and pharmacist if you are allergic to levothyroxine, thyroid hormone, any other drugs, povidone iodine, tartrazine (a yellow dye in some processed foods and drugs), or foods such as lactose or corn starch. Levothroid contains lactose, while Synthroid contains tartrazine and povidone. tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially amphetamines; anticoagulants ('blood thinners') such as warfarin (Coumadin); antidepressants or anti-anxiety agents; arthritis medicine; aspirin; beta-blockers such as metoprolol (Lopressor, Toprol), propranolol (Inderal) or timolol (Blocadren, Timoptic); cancer chemotherapy agents; diabetes medications (insulin and tablets); digoxin (Lanoxin); estrogens; methadone; oral contraceptives; phenytoin (Dilantin); steroids; theophylline (TheoDur); and vitamins. if you take an antacid, calcium carbonate (Tums), cholestyramine (Questran), colestipol (Colestid), iron, orlistat (alli, Xenical), simethicone (Phazyme, Gas X), sodium polystrene sulfonate (Kayexalate), or sucralfate (Carafate), take it at least 4 hours before or 4 hours after you take levothyroxine. tell your doctor if you have or have ever had diabetes; hardening of the arteries (atherosclerosis); kidney disease; hepatitis; cardiovascular disease such as high blood pressure, chest pain (angina), arrhythmias, or heart attack; or an underactive adrenal or pituitary gland. if you have surgery, including dental surgery, tell the doctor or dentist that you are taking levothyroxine.

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911.