Factitious hyperthyroidism is higher-than-normal thyroid hormone levels in the blood that occur from taking too much thyroid hormone medication.
The thyroid gland produces the hormones thyroxine (T4) and triiodothyronine (T3). In most cases of hyperthyroidism, the thyroid gland itself produces too much of these hormones.
Hyperthyroidism can also be caused by taking too much thyroid hormone medication for hypothyroidism. This is called factitious hyperthyroidism. When this occurs because the prescribed dosage of hormone medication is too high, it is called iatrogenic, or doctor-induced, hyperthyroidism.
Factitious hyperthyroidism can also occur when a patient intentionally takes too much thyroid hormone, such as in people:
Children may take thyroid hormone pills accidentally.
In rare cases, factitious hyperthyroidism is caused by eating meat contaminated with thyroid gland tissue.
The symptoms of factitious hyperthyroidism are the same as those of hyperthyroidism caused by the thyroid gland, except that:
Tests used to diagnose factitious hyperthyroidism include:
You must stop taking thyroid hormone. If you need to take this medicine, you will have to reduce the dosage.
You should be re-checked in 2 - 4 weeks to be sure that the signs and symptoms of hyperthyroidism are gone. This also helps to confirm the diagnosis.
People with Munchausen syndrome will need mental health treatment and follow-up.
Factitious hyperthyroidism will clear up on its own when you stop taking or lower the dosage of thyroid hormone.
When factitious hyperthyroidism lasts a long time, patients are at risk of having the same complications as untreated or improperly treated hyperthyroidism caused by the thyroid gland.
These complications include:
Contact your health care provider if you experience any of the symptoms of hyperthyroidism.
Thyroid hormone should be taken only by prescription and under the supervision of a doctor.
Factitious thyrotoxicosis; thyrotoxicosis factitia; thyrotoxicosis medicamentosa
Mandel SJ, Larsen PR, Davies TF. Thyrotoxicosis. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 12th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 12.
Updated by: Yi-Bin Chen, MD, Leukemia/Bone Marrow Transplant Program, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2014, A.D.A.M., Inc. Duplication for commercial use must be authorized in writing by ADAM Health Solutions.