Desiccated (dried) thyroid is a combination of hormones that are normally produced by your thyroid gland to regulate the body's energy and metabolism. Desiccated thyroid is given when the thyroid does not produce enough of this hormone on its own.

Desiccated thyroid treats hypothyroidism (low thyroid hormone). Desiccated thyroid is also used to treat or prevent goiter (enlarged thyroid gland), and is also given as part of a medical tests for thyroid disorders.

Desiccated thyroid should not be used to treat obesity or weight problems.

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

You may not be able to use Nature-Throid if you have a thyroid disorder called thyrotoxicosis, or an adrenal gland problem that is not controlled by treatment.

Call your doctor if you have signs of thyroid toxicity, such as chest pain, fast or pounding heartbeats, feeling hot or nervous, or sweating more than usual.

Follow all directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results. Do not use Nature-Throid in larger or smaller amounts or for longer than recommended.

While using desiccated thyroid, you may need frequent blood tests.

Keep using this medicine as directed, even if you feel well. You may need to take thyroid medication for the rest of your life.

Call your doctor if you notice any signs of thyroid toxicity, such as chest pain, fast or pounding heartbeats, feeling hot or nervous, or sweating more than usual.

If you need surgery, tell the surgeon ahead of time that you are using desiccated thyroid. You may need to stop using the medicine for a short time.

Store at room temperature away from moisture and heat.

Since thyroid hormone occurs naturally in the body, almost anyone can take desiccated thyroid. However, you may not be able to use this medication if you have a thyroid disorder called thyrotoxicosis, or an adrenal gland problem that is not controlled by treatment.

To make sure desiccated thyroid is safe for you, tell your doctor if you have:

• heart disease, angina (chest pain);

• coronary artery disease;

• congestive heart failure;

• any type of diabetes; or

• problems with your adrenal gland.

Desiccated thyroid is not expected to be harmful to an unborn baby, but your dose needs may be different during pregnancy. Tell your doctor if you become pregnant while taking this medicine.

Small amounts of desiccated thyroid can pass into breast milk, but this is not expected to harm a nursing baby. However, do not use this medication without telling your doctor if you are breast-feeding a baby.

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.

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

If you also take cholestyramine (Prevalite, Questran) or colestipol (Colestid), avoid taking these medications within 4 hours before or after you take desiccated thyroid.

Avoid taking an antacid within 4 hours before or after you take desiccated thyroid. Some antacids can make it harder for your body to absorb desiccated thyroid.

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

Common side effects may include temporary hair loss (especially in children).

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.

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with desiccated thyroid, especially:

• birth control pills or hormone replacement therapy;

• a blood thinner such as warfarin, Coumadin, Jantoven;

• insulin or diabetes medication you take by mouth;

• medications that contain iodine (such as I-131);

• salicylates such as aspirin, Nuprin Backache Caplet, Kaopectate, KneeRelief, Pamprin Cramp Formula, Pepto-Bismol, Tricosal, Trilisate; or

• steroids such as prednisone and others.

This list is not complete. Other drugs may interact with desiccated thyroid, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.