7 mins read

Overview: Desiccated thyroid is used as a replacement hormone therapy for people with low thyroid hormone levels, among other uses. It supplies thyroid hormone to patients who do not make enough. Desiccated thyroid interacts with many medicines and health conditions. Always make sure your health care provider knows all of your health conditions and medicines you are taking, including over-the-counter (OTC) products.

Uses

What is desiccated thyroid used for?

Desiccated thyroid is commonly used for the following conditions.

Desiccated thyroid may also be used for other conditions as determined by your health care provider.

Note: The FDA has not found this medicine to be safe and effective, and the label is not approved by the FDA. Learn more about unapproved drugs.

How does desiccated thyroid work (mechanism of action)?

Desiccated thyroid contains both levothyroxine (T4) and liothyronine (T3), which are thyroid hormones found in the body. This medicine provides a source of thyroid hormones in people who do not make enough on their own.

Desiccated thyroid may also be used in people with certain conditions, such as goiter or thyroid cancer, that cause the thyroid to grow too much. Taking this medicine tells the thyroid to stop producing its own hormones, which can help to stop the growth of the thyroid gland or thyroid cancer.

How is desiccated thyroid supplied (dosage forms)?

Brands and other names

  • Adthyza Thyroid
  • Armour Thyroid
  • NP Thyroid

Dosage forms and strengths

  • 15 mg, 16.25 mg, 30 mg, 32.5 mg, 60 mg, 65 mg, 90 mg, 97.5 mg, 120 mg, 130 mg, 180 mg, 240 mg, 300 mg oral tablets

How should I store desiccated thyroid?

Desiccated thyroid should be stored at room temperature, between 59 F to 86 F (15 C to 30 C). Store it in a tight container, protected from light and moisture.

Side Effects

What are the most common side effects of desiccated thyroid?

The most common side effects of desiccated thyroid are listed below. Tell your health care provider if you have any of these side effects that bother you.

  • Arrhythmias, which are abnormal heart rhythms
  • Heart attack
  • Shortness of breath
  • Headache
  • Nervousness
  • Irritability
  • Trouble sleeping
  • Tremors
  • Muscle weakness
  • Increased appetite
  • Weight loss
  • Diarrhea
  • Trouble tolerating heat
  • Menstrual changes
  • Skin rash

There may be other side effects of desiccated thyroid that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of desiccated thyroid?

While less common, the most serious side effects of desiccated thyroid are described below, along with what to do if they happen.

Severe Allergic Reactions. Desiccated thyroid may cause allergic reactions, which can be serious. Stop taking desiccated thyroid and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Heart Problems. Desiccated thyroid may cause your heart rate to increase or become abnormal. You may also have chest pain. Your risk may be higher if you are older, have heart problems, or if you take too much desiccated thyroid. Tell your health care provider right away if you notice any of the following.

  • Chest pain or pressure
  • Fast or abnormal heartbeat
  • Shortness of breath

Weak Bones. Desiccated thyroid may cause your bones to become weaker, leading to reduced bone density (osteopenia). It may also cause a more serious condition called osteoporosis, which can cause your bones to break (fracture) more easily. You may be at higher risk of this if you take too much desiccated thyroid or if you have gone through menopause. Tell your health care provider if you break a bone, and get a bone mineral density test if one is ordered for you.

Warnings & Precautions

Who should not use desiccated thyroid?

Allergies to Ingredients. People who are allergic to any of the following should not take desiccated thyroid.

  • Adthyza Thyroid
  • Armour Thyroid
  • Desiccated thyroid
  • NP Thyroid
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific desiccated thyroid products they stock.

Reduced Adrenal Function (Adrenal Insufficiency). You should not take desiccated thyroid If you have reduced adrenal function that is not being treated. 

Thyrotoxicosis. You should not take a desiccated thyroid if you have too much thyroid hormone in your blood (thyrotoxicosis).

What should I know about desiccated thyroid before using it?

Do not take desiccated thyroid unless it has been prescribed to you by a health care provider. Take it as prescribed. You should not take desiccated thyroid to lose weight or for obesity.

Do not share desiccated thyroid with other people, even if they have the same condition as you. It may harm them.

Keep desiccated thyroid out of the reach of children.

Older people may be at greater risk for some side effects from desiccated thyroid. Talk to your health care provider about your risks if you are 65 or older. 

You may notice hair loss while taking desiccated thyroid, especially when you first start taking it. This is rare and the hair loss is usually temporary. 

What should I tell my health care provider before using desiccated thyroid?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if desiccated thyroid is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your health care provider if you have any of the following. 

  • Any food allergies
  • Heart or blood vessel disease
  • Reduced adrenal function
  • Diabetes
  • Thyroid nodules
  • Myxedema coma
  • Low red blood cell levels (anemia)
  • Weak bones (osteoporosis)
  • Recently received radiation therapy with iodine
  • You are postmenopausal
  • Upcoming surgery or dental procedures
  • Pituitary problems
  • Clotting problems

Pregnancy. It is not known if or how desiccated thyroid could affect pregnancy or harm an unborn baby. Tell your health care provider if you are or plan to become pregnant. Your health care provider will advise you if you should take desiccated thyroid while you are pregnant or trying to get pregnant. If you continue taking desiccated thyroid during pregnancy, your health care provider may monitor your thyroid levels more often.

Breastfeeding. Desiccated thyroid passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed. Your health care provider will advise you if you should take desiccated thyroid while breastfeeding.

Other Medicines and Supplements. Desiccated thyroid may interact with other medicines and supplements. Before taking desiccated thyroid, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Interactions

Does desiccated thyroid interact with foods or drinks?

It is important to take desiccated thyroid the same way each day. It should be taken on an empty stomach at least one-half to one hour before your first meal of the day. 

Certain foods may affect the amount of desiccated thyroid that is absorbed into the body. Talk with your health care provider about how the following foods can affect your blood levels of desiccated thyroid. 

  • Soybean flour (infant formula)
  • Cottonseed meal
  • Walnuts
  • Dietary fiber
  • Grapefruit juice

It is unknown if drinking alcohol will affect desiccated thyroid.

Does desiccated thyroid interact with other medicines (drug interactions)?

Desiccated thyroid interacts with many other medicines. Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before taking desiccated thyroid.

  • Certain OTC vitamins/minerals such as calcium carbonate and ferrous sulfate
  • Orlistat, which is used for weight loss
  • A bile acid sequestrant, such as colestipol (Colestid), cholestyramine (Prevalite), or colesevelam (Welchol), which is a medicine to lower cholesterol
  • Kayexalate, which is a medicine used to treat high potassium in the blood
  • Sevelamer, which is a medicine used to treat high phosphate in the blood
  • A proton pump inhibitor (PPI), such as esomeprazole (Nexium), lansoprazole (Prevacid), omeprazole (Prilosec), pantoprazole (Protonix), or rabeprazole (Aciphex)
  • An antacid (or supplement or laxative) containing calcium, aluminum, magnesium, iron, or simethicone
  • A hormone, such as estrogen (in birth control pills and hormone replacement therapy) or testosterone
  • Methadone, which is an opioid medicine used to treat pain or opioid use disorder
  • 5-fluorouracil (5-FU), asparaginase, mitotane, tamoxifen, or a medicine known as a tyrosine-kinase inhibitor, which are used to treat or prevent certain cancers
  • A corticosteroid, which is a medicine for certain inflammatory conditions
  • Slow-release nicotinic acid, which is a medicine used to treat high cholesterol
  • A salicylate, such as diflunisal or salsalate, which is a medicine used for osteoarthritis or rheumatoid arthritis
  • Any medicine for seizures, such as carbamazepine, phenobarbital, or phenytoin
  • Furosemide, which is a diuretic, also called a water pill. This is a medicine used to reduce edema (fluid retention) and blood pressure
  • A nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen, naproxen, and others, which are contained in many prescription and OTC products for pain, swelling, and fever
  • Rifampin, which is a medicine used to treat certain infections
  • A beta-blocker, such as atenolol (Tenormin), metoprolol (Lopressor, Toprol XL, and others), or propranolol (Inderal LA, Innopran XL), which is a medicine that may be used for certain heart conditions or to lower blood pressure
  • Amiodarone (Pacerone and others), which is a medicine used for an irregular heart rhythm
  • Digoxin (Lanoxin), which is a medicine used to treat irregular heartbeat and some types of heart failure
  • A medicines for diabetes
  • A blood thinner, which is a medicine used to treat or prevent blood clots
  • A tricyclic antidepressant or tetracyclic antidepressant, even if it is not used for depression
  • A weight loss medication, such as diethylpropion, phendimetrazine, or phentermine (Adipex-P, Lomaira, Qsymia)

Some other medicines may alter the blood levels of desiccated thyroid. Tell your health care provider about all medicines that you take or have recently taken.

This may not be a complete list of medicines that can interact with desiccated thyroid. Always check with your health care provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much desiccated thyroid?

If you or someone else has used too much desiccated thyroid, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of desiccated thyroid?

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.