Related Terms

  • Armour Thyroid®, Bio-Throid®, desiccated thyroid, desiccated thyroid extract, dry thyroid extract, glandular, glandular thyroid, homologous thyroid gland, human crude thyroid extract, hyperthyroidism, hypothyroidism, levothyroxine, levothyroxine sodium, liothyronine, LOCO X112, L-thyroxine, natural thyroid, natural thyroid hormone, Nature-Throid, Naturethroid®, raw thyroid, T3, T4, Thyranon, thyreoideum, thyroid BP, thyroid subcellular fractions, thyroid USP, Thyroideum siccum, thyroxine, triiodothyronine, Westhroid®.

Background

  • Thyroid extracts are derived from animal thyroid tissue. Thyroid extract is a type of glandular nutritional supplementation that refers to dried and ground-up raw animal tissues or extracts of these tissues. Desiccated thyroid, such as the brand Armour® Thyroid, is derived from animal tissues, typically bovine or porcine thyroid. It contains both liothyronine (T3) and levothyroxine (T4).
  • Glandulars and other tissue extracts have played roles in traditional medicine since the late 1800s. Glandular therapy originated from the practice of eating the whole gland. Glandulars are thought to improve the function of the specific gland consumed. Early reports (1891) have suggested successful treatment of hypothyroidism with thyroid extracts. This practice originated in Europe and spread quickly to the United States. Desiccated thyroid or thyroid extract is still used by some practitioners, but most practitioners now use synthetic T4 or a combination of synthetic T4 and T3.
  • Thyroid hormones increase the rates of growth and metabolism and thereby increase respiratory rate, body temperature, heart rate, reproductive behavior, and energy use.
  • Although thyroid extract has been traditionally used to replace patients’ normal thyroid activity, limited study does not support the use of thyroid extract for hypothyroidism (underactive thyroid).

Evidence Table

    Disclaimer

    These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

    Cancer (thyroid)

    Thyroid extract has been used traditionally to replace patients’ normal thyroid activity. Limited study suggests that thyroid extract may increase survival in patients with thyroid cancer. More studies are needed in this area before conclusions can be made.

    Hypothyroidism (underactive thyroid gland)

    Thyroid extract has been used traditionally to replace patients’ normal thyroid activity. Limited study does not support the use of thyroid extract for hypothyroidism. More studies are needed in this area before conclusions can be made.

    Infertility

    Based on human study, thyroid extract may increase the incidence of pregnancy in infertile patients due to luteal-phase deficiency. More studies are needed in this area before conclusions can be made.

*Key to grades:

Tradition

    Disclaimer

    The below uses are based on tradition, scientific theories, or limited research. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider. There may be other proposed uses that are not listed below.

Dosing

    Disclaimer

    The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

  • Adults (18 years and older)

    • Various doses have been studied, but there is no proven effective dose for thyroid extract. The following doses of thyroid extract have been used: 50 milligrams of thyroid extract daily and 100 milligrams of Thyranon® daily for four months.
  • Children (under 18 years old)

    • There is no proven safe or effective dose for thyroid extract in children.

Safety

    Disclaimer

    The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

  • Allergies

    • Avoid with known or potential allergy/hypersensitivity to desiccated thyroid or thyroid extract.
  • Side Effects and Warnings

    • Tachycardia, palpitations, arrhythmias, angina (chest pain), skin reactions, changes in appetite, diarrhea, nausea, vomiting, hair loss, bone loss, headache, irritability, leg cramps, tremors, trouble sleeping, weight loss, and fever have been reported.
    • Avoid in the treatment of obesity.
    • Avoid in patients with uncontrolled high blood pressure or uncontrolled angina.
    • Use cautiously in patients with sensitive skin.
    • Use cautiously in postmenopausal women.
    • Use cautiously in patients with hormonal disorders, such as low levels of pituitary hormone.
    • Use cautiously in patients with diabetes or in those taking medications for diabetes.
    • Use cautiously in patients taking anticoagulants (“blood thinners”) or antiplatelets.
    • Use cautiously in elderly patients.
    • Use cautiously in children.
    • Use cautiously during pregnancy and breastfeeding.
  • Pregnancy and Breastfeeding

    • Thyroid hormones are considered safe during pregnancy (FDA Pregnancy Category A); however, there is limited available evidence regarding the safety of thyroid extract.

Interactions

    Disclaimer

    Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

  • Interactions with Drugs

    • Thyroid extracts may increase the risk of bleeding when taken with drugs that increase the risk of bleeding. Some examples include aspirin, anticoagulants (“blood thinners”) such as warfarin (Coumadin®) or heparin, anti-platelet drugs such as clopidogrel (Plavix®), and non-steroidal anti-inflammatory drugs (NSAIDS) such as ibuprofen (Motrin®, Advil®) or naproxen (Naprosyn®, Aleve®).
    • Thyroid extracts may increase blood sugar levels. Patients taking drugs for diabetes by mouth or insulin should be monitored closely by their qualified healthcare professionals, including pharmacists. Medication adjustments may be necessary.
    • Thyroid extracts may interfere with the way the body processes certain drugs using the liver’s “cytochrome P450” enzyme system. As a result, the levels of drugs may be increased in the blood and may cause increased effects or potentially serious adverse reactions. Patients using any medications should check the package inserts, and speak with their qualified healthcare professionals, including pharmacists, about possible interactions.
    • Thyroid extracts may elevate digoxin levels in patients taking digoxin, thereby increasing the risk of toxicity.
    • Thyroid extracts may enhance the immune system. Use cautiously with agents that may stimulate or suppress the immune system.
    • Thyroid extracts may alter the effects of amiodarone, antacids, antidepressant agents, cholesterol-lowering drugs, antiobesity drugs, barbiturates, calcium salts, carbamazepine, corticosteroids, hormonal drugs, iron salts, ketamine, rifamycins, sucralfate, ympathomimetics, and theophylline.
  • Interactions with Herbs and Dietary Supplements

    • Thyroid extracts may increase the risk of bleeding when taken with herbs or supplements that increase the risk of bleeding.
    • Thyroid extracts may increase blood sugar levels. Patients taking herbs or supplements for diabetes by mouth or insulin should be monitored closely by their qualified healthcare professionals, including pharmacists.
    • Thyroid extracts may interfere with the way the body processes certain herbs or supplements using the liver’s “cytochrome P450” enzyme system. As a result, the levels of drugs may be increased in the blood, and may cause increased effects or potentially serious adverse reactions. Patients using any medications should check the package inserts, and speak with their qualified healthcare professionals, including pharmacists, about possible interactions.
    • Thyroid extracts may enhance the immune system. Use cautiously with herbs or supplements that may stimulate or suppress the immune system.
    • Thyroid extracts may alter the effects of achyranthes aspera, aloe vera, antacids, antidepressants, antiobesity agents, antioxidants, ashwagandha (Withania somnifera), bacopa monnieri, bael fruit (Aegle marmelos), bauhinia purpurea, betel leaf extract, bugleweed (Lycopus europaeus L.), calcium supplements, cardiac glycosides, convulvulus pluricaulis, fenugreek seed extract (Trigonella foenum-graecum), flavonoids, green tea, garlic (Allium sativum), guggul (Commiphora mukul), holy basil (Ocimum sanctum leaf extract), iodine, iron salts, kalanchoe brasiliensis, lithospermum officinale, magnesium supplements, moringa oleifera, neem (Azardirachta indica), olive leaf (Olea europaea), phytoestrogens, rapeseed, seaweed, kelp, bladderwrack, soy, and steroids.

Attribution

  • This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration ().

Bibliography

    Disclaimer

    Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to . Selected references are listed below.

  • Mazer, NA. Interaction of estrogen therapy and thyroid hormone replacement in postmenopausal women. Thyroid 2004;14 Suppl 1:S27-S34.
    View Abstract
  • Roberts, CG and Ladenson, PW. Hypothyroidism. Lancet 3-6-2004;363(9411):793-803.
    View Abstract
  • Uzzan, B, Campos, J, Cucherat, M, et al. Effects on bone mass of long term treatment with thyroid hormones: a meta-analysis. J Clin Endocrinol Metab 1996;81(12):4278-4289.
    View Abstract