Common uses

This medicine is a thyroid hormone used to treat hypothyroidism. It may also be used to treat other conditions as determined by your doctor.

Before using

Warning: this medicine should not be used either alone or in combination with diet pills to treat obesity or for weight loss because serious, even life-threatening, effects could occur. Large doses of this medicine, especially with diet pills, may cause symptoms of toxicity. (see possible side effects and overdose sections for more information). Some medicines or medical conditions may interact with this medicine.

Additional monitoring of your dose or condition may be needed if you are taking warfarin, digoxin, estrogen products (including estrogen-containing birth control pills), diabetes medicines (e.g., insulin, glipizide, rosiglitazone), amiodarone, iodide (including radiographic contrast agents containing iodine), lithium, anti-thyroid agents (e.g., methimazole, propylthiouracil), androgens or anabolic steroids, glucocorticoids (e.g., dexamethasone, prednisone), high dose salicylates (e.g., aspirin), phenobarbital, rifamycins (e.g., rifampin), beta-blockers (e.g., propranolol), antidepressants (e.g., amitriptyline, maprotiline, sertraline), cytokines (e.g., interferon-alpha, interleukin-2), growth hormones, ketamine, theophylline.

Inform your doctor of any other medical conditions including heart problems (e.g., hypertension, congestive heart failure, arrhythmias, coronary artery disease), diabetes, male or female infertility problems, bone loss (osteoporosis), other hormone disorders, other thyroid problems, blood clotting disorders, allergies, pregnancy, or breast-feeding.

Use of this medicine is not recommended if you have a history of overactive thyroid condition (e.g., thyrotoxicosis), a heart attack (acute myocardial infarction), or adrenal gland problems (e.g., uncorrected adrenal insufficiency).

Directions

Take this medicine on an empty stomach at least 1 hour before or 2 to 3 hours after eating. It is recommended that you take your dose 1 hour before breakfast unless otherwise directed by your doctor.

Try to take this medicine at the same time each day. This medicine works best when there is a constant level of the drug in your body. For children who cannot swallow whole tablets, crush the tablet and mix in 1 or 2 teaspoons (5 or 10 ml) of water, and give using a spoon or dropper as soon as possible after preparation. Do not store the mixture for later use. Do not mix crushed tablets in soybean infant formula.

Some medicines may decrease the absorption of this medicine into your bloodstream. Therefore, take this medicine 4 hours apart from calcium supplements, iron, antacids (those containing aluminum, calcium, or magnesium), simethicone, cholestyramine, colestipol, sucralfate, or sodium polystyrene sulfonate.

Store this medicine at room temperature in a tightly-closed container, away from heat, moisture, and light. If you miss a dose of this medicine, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Cautions

Continuous use of this medicine for a few weeks may be necessary to relieve symptoms of your condition. Symptoms of low thyroid hormone levels include fatigue, muscle aches, constipation, dry skin, weight gain, slow heart rate, sensitivity to cold, or dry brittle hair that tends to fall out easily. These symptoms should disappear as your body adjusts to the medicine. If they persist or become bothersome, notify your doctor promptly as your dose may need to be adjusted. Do not adjust your dose or stop taking this medicine without checking with your doctor.

Tell the doctor or dentist that you are taking this medicine before you have emergency treatment or surgery. Keep all doctor and laboratory appointments (e.g., thyroid function tests) while you are taking this medicine. Before you begin taking any new medicine, either prescription or over-the-counter, check with your doctor or pharmacist. This includes calcium or aluminum-containing antacids, iron preparations and cough-and-cold products, or diet aids.

Caution is advised when using this medicine in the elderly because they may be more sensitive to the effects of this medicine. Caution is advised when using this medicine in children because overuse may reduce the child's final adult height. For women: inform your doctor if you become pregnant, as your dose may need to be adjusted. This medicine is excreted in breast milk. Consult your doctor before breast-feeding.

Possible side effects

Side effects that may occur while taking this medicine include headache, nervousness, trembling, sweating, increased appetite, diarrhea, weight loss or insomnia. If they continue or are bothersome, check with your doctor as your dose may need to be adjusted. In rare instances, some hair loss may occur during the first few months of starting this medicine. This effect is usually temporary as your body adjusts to this medicine. If this effect persists or worsens, notify your doctor as soon as possible.

Contact your doctor immediately if you experience chest pain, rapid or irregular heartbeat, shortness of breath, or seizures. An allergic reaction to this medicine is unlikely, but if you experience difficulty breathing; tightness of chest; swelling of eyelids, face, or lips; or if you develop a rash or hives, tell your doctor immediately. If you notice other effects not listed above, contact your doctor or pharmacist.

If you take too much

If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include excessive sweating, extreme nervousness, irregular heartbeat, chest pain, or seizures.

Additional information

Do not share this medicine with others for whom it was not prescribed. Do not use this medicine for other health conditions. Keep this medicine out of the reach of children and pets. If using this medicine for an extended period of time, obtain refills before your supply runs out.

Drug interactions

Drug interactions can result in unwanted side effects or prevent a medicine from doing its job. Some medicines or medical conditions may interact with this medicine. Inform your doctor or pharmacist of all prescription and over-the-counter medicine that you are taking.

What is/are Synthroid Tablets?

LEVOTHYROXINE is a thyroid hormone. This medicine can improve symptoms of thyroid deficiency such as slow speech, lack of energy, weight gain, hair loss, dry skin, and feeling cold. It also helps to treat goiter (an enlarged thyroid gland). This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

What should I tell my health care providers before I take this medicine?

They need to know if you have any of these conditions:

How should I use this medicine?

Take this medicine by mouth with plenty of water. It is best to take on an empty stomach, at least 30 minutes before or 2 hours after food. Follow the directions on the prescription label. Take at the same time each day. Do not take your medicine more often than directed.

Contact your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children and infants as young as a few days of age for selected conditions, precautions do apply. For infants, you may crush the tablet and place in a small amount of (5-10 ml or 1 to 2 teaspoonfuls) of water, breast milk, or non-soy based infant formula. Do not mix with soy-based infant formula. Give as directed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

Note: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses. What may interact with this medicine?

This list may not describe all possible interactions. Give your health care providers a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What side effects may I notice from this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

This list may not describe all possible side effects.

What should I watch for while using this medicine?

Be sure to take this medicine with plenty of fluids. Some tablets may cause choking, gagging, or difficulty swallowing from the tablet getting stuck in your throat. Most of these problems disappear if the medicine is taken with the right amount of water or other fluids.

Do not switch brands of this medicine unless your health care professional agrees with the change. Ask questions if you are uncertain.

You will need regular exams and occasional blood tests to check the response to treatment. If you are receiving this medicine for an underactive thyroid, it may be several weeks before you notice an improvement. Check with your doctor or health care professional if your symptoms do not improve.

It may be necessary for you to take this medicine for the rest of your life. Do not stop using this medicine unless your doctor or health care professional advises you to.

This medicine can affect blood sugar levels. If you have diabetes, check your blood sugar as directed.

You may lose some of your hair when you first start treatment. With time, this usually corrects itself.

If you are going to have surgery, tell your doctor or health care professional that you are taking this medicine.

Where should I keep this medicine?

Keep out of the reach of children.