Thyrotoxicosis factitia (TF) is also known as thyroxine addict or metabolic malingerer [1] [2] syndrome. It occurs in patients who are prescribed a very high dose of thyroid hormones as medication (iatrogenic); or those who consume thyroid hormone medication surreptitiously for weight loss or to increase their energy levels or to decrease sleep but deny taking the medication (intentional); or in children (accidental) or adults who consume meat containing thyroid tissue (accidental).

Clinical presentation of TF is identical to thyrotoxicosis except that patients with TF do not have a goiter (thyromegaly) and unlike patients with Grave's disease, they have neither exophthalmos nor myxedema (thickened skin over their shins). Features of thyrotoxicosis like anxiety, hyperactivity, increased perspiration, dyspnea, intolerance to heat, unexplained weight loss, diarrhea, fine tremors, hyperreflexia, tremulousness, palpitations and atrial fibrillation are seen in TF too. Complications like cardiac arrhythmias, hypermetabolism, hyperpyrexia, thyroid storm and myocardial infarction have been reported in TF [3] [4].

• Weight Loss

  It occurs in patients who are prescribed a very high dose of thyroid hormones as medication (iatrogenic); or those who consume thyroid hormone medication surreptitiously for weight loss or to increase their energy levels or to decrease sleep but deny [symptoma.com]

  In our case thyroxine was abused for weight loss and energy boost up causing junctional arrhythmias leading to cardiac arrest. [tandfonline.com]

  loss preparation Clinical findings: (1) There are clinical signs of thyrotoxicosis, depending on hormone exposure, except that ophthalmopathy is absent. (2) The thyroid gland is usually not enlarged. [meducator3.net]

  They may include Being nervous or irritable Mood swings Fatigue or muscle weakness Heat intolerance Trouble sleeping Hand tremors Rapid and irregular heartbeat Frequent bowel movements or diarrhea Weight loss Goiter, which is an enlarged thyroid that [icdlist.com]

• Fever

  Fever should not be treated with cooling mattresses, and Tylenol is ineffective. Fever may be controlled with Demerol (25-50 mg intravenously Q 6 hours) and chlorpromazine (25-50 mg intravenously Q 6 hours). [thebigl.co]

  In subacute (De Quervain's) thyroiditis symptoms patients may have fever in the initial phase and the thyroid is tender. [jiscmail.ac.uk]

  Agranulocytosis occurs in 1 in 300 patients treated with thionamides and presents as a sore throat, mouth ulcers and high fever. [statpearls.com]

  It usually causes fever and pain in the neck, jaw or ear. [nhs.uk]

  Rarely, methimazole or propylthiouracil may cause fever, sore throat, or other signs of infection. If you develop these symptoms, contact your doctor immediately. [medicinenet.com]

• Heat Intolerance

  They may include Being nervous or irritable Mood swings Fatigue or muscle weakness Heat intolerance Trouble sleeping Hand tremors Rapid and irregular heartbeat Frequent bowel movements or diarrhea Weight loss Goiter, which is an enlarged thyroid that [icdlist.com]

  In Europe, it affects around 1 in 2000 people annually. 1 Although thyrotoxicosis typically presents with weight loss, heat intolerance, and palpitations, there are a large variety of additional features, which manifest more variably with advancing age [doi.org]

  Signs and symptoms vary between people and may include irritability, muscle weakness, sleeping problems, a fast heartbeat, heat intolerance, diarrhea, enlargement of the thyroid, and weight loss. [dbpedia.org]

• Rigor

  When MMI, thyroidectomy, and 131 I cannot be used, PTU can be considered an option for a short period of time in doses of 4.7-8.6 mg/kg of body weight (116) ( B ) under rigorous clinical and laboratory monitoring (see below). [scielo.br]

• Diarrhea

  Features of thyrotoxicosis like anxiety, hyperactivity, increased perspiration, dyspnea, intolerance to heat, unexplained weight loss, diarrhea, fine tremors, hyperreflexia, tremulousness, palpitations and atrial fibrillation are seen in TF too. [symptoma.com]

  They may include Being nervous or irritable Mood swings Fatigue or muscle weakness Heat intolerance Trouble sleeping Hand tremors Rapid and irregular heartbeat Frequent bowel movements or diarrhea Weight loss Goiter, which is an enlarged thyroid that [icdlist.com]

  Signs and symptoms vary between people and may include irritability, muscle weakness, sleeping problems, a fast heartbeat, heat intolerance, diarrhea, enlargement of the thyroid, and weight loss. [dbpedia.org]

• Increased Appetite

  appetite Hyperkinesia Sweating Heat intolerance Palpitations Tremor Irritability Oligomenorrhoea Infertility Psychosis, panic Lost libido Tall kids Grave's only eye signs pretibial myoedema Grave's demopathy thyroid acropachy extreme cases; soft tissue [alancam.com]

  Common symptoms of hyperthyroidism include restlessness, agitation, anxiety, tremors, weight loss despite an increased appetite, sweating, rapid heart rate, intolerance to heat, and frequent bowel movements. [medicinenet.com]

  These can include diarrhoea, weight loss (although around 10% develop weight gain due to increased appetite), shaking or tremor (notably in the hands), sweating, increased heart rate that can be felt by the patient (palpitations), overactivity, agitation [yourhormones.info]

  appetite, heat intolerance with increased sweating, palpitations, tremor, anxiety, proximal muscle weakness, alopecia and increased fatigability. [statpearls.com]

  In patients with Graves’ disease, the following symptoms and signs may be present: Symptoms weight loss heat intolerance fatigue hair loss irritability restlessness lack of concentration insomnia labile emotion palpitations exertional dyspnea increased [clinicaladvisor.com]

• Regurgitation

  Mild mitral, tricuspid regurgitation. [ncbi.nlm.nih.gov]

  There was mild mitral and tricuspid regurgitation. Chest X-ray showed mixed interstitial and alveolar opacities within the mid and upper lung zones, more on the left side with no cardiomegaly or mediastinal shifting. [tandfonline.com]

• Food Intolerance

  He always had a fried and fatty food intolerance which produced “gas and sour stomach.” For three months he had infrequent attacks of watery diarrhea without cramps or gross blood. [kundoc.com]

• Tachycardia

  Other types of arrhythmias can be sinus tachycardia, ventricular tachycardia, SVT, ventricular fibrillation and rarely cardiac arrest can also happen [13–15]. [tandfonline.com]

  An esmolol infusion was started to control his persistent tachycardia but this depressed his myocardial contractility. He required amrinone and noradrenaline infusions as further inotropic support. [paperity.org]

  Conclusion Thyroxine induced cardiac arrhythmias can range from sinus tachycardia to ventricular fibrillation, and surprisingly it can cause junctional rhythm due to an unknown mechanism. [onlinejacc.org]

  Features of MyAccess include: Remote Access Favorites Save figures into PowerPoint Download tables as PDFsGo to My Dashboard Close Sweating, weight loss or gain, anxiety, palpitations, loose stools, heat intolerance, fatigue, menstrual irregularity Tachycardia [accessmedicine.mhmedical.com]

• Muscle Tenderness

  tenderness Present Present Skin Increased perspiration Warm and moist skin Present Present Graves dermopathy Red, swollen skin on shins and top of feet Orange peel like skin called pretibial myxedema Present in Graves disease Absent Ocular Redness and [ncbi.nlm.nih.gov]

• Denial

  We are receiving denials that this provider type may not bill for t... [ Read More ] Are there new CMS CCI edits for billing out 93312, 93320 & 93325 for anesthesiologists. We are getting denials from all insurance providers when we bill for these. [coder.aapc.com]

• Tremor

  Features of thyrotoxicosis like anxiety, hyperactivity, increased perspiration, dyspnea, intolerance to heat, unexplained weight loss, diarrhea, fine tremors, hyperreflexia, tremulousness, palpitations and atrial fibrillation are seen in TF too. [symptoma.com]

  They may include Being nervous or irritable Mood swings Fatigue or muscle weakness Heat intolerance Trouble sleeping Hand tremors Rapid and irregular heartbeat Frequent bowel movements or diarrhea Weight loss Goiter, which is an enlarged thyroid that [icdlist.com]

  Access Favorites Save figures into PowerPoint Download tables as PDFsGo to My Dashboard Close Sweating, weight loss or gain, anxiety, palpitations, loose stools, heat intolerance, fatigue, menstrual irregularity Tachycardia; warm, moist skin; stare; tremor [accessmedicine.mhmedical.com]

• Hyperreflexia

  Features of thyrotoxicosis like anxiety, hyperactivity, increased perspiration, dyspnea, intolerance to heat, unexplained weight loss, diarrhea, fine tremors, hyperreflexia, tremulousness, palpitations and atrial fibrillation are seen in TF too. [symptoma.com]

  and testicular malignancies may cause hyperthyroidism Heat intolerance, sweating Palpitations Pruritus Frequent bowel movements Weight loss (or gain) Menstrual irregularities Nervousness, fine resting tremor Fatigue Muscle weakness, muscle cramps, hyperreflexia [accessmedicine.mhmedical.com]

  Her physician found no obvious tremors, hyperdynamic apex, or hyperreflexia on physical exam. To rule out laboratory error from the second set of tests, her physician ordered yet another round of blood work. [mdedge.com]

  […] hyperthyroid state Cardiovascular heat intolerance, sweating, and polydipsia, palpitations, Tachycardia, systolic hypertension, atrial fibrillation, weight loss Present Present Neuromuscular Tremors, anxiety, Reduced sleep, Nervousness Hyperactivity, Hyperreflexia [ncbi.nlm.nih.gov]

• Tremulousness

  Features of thyrotoxicosis like anxiety, hyperactivity, increased perspiration, dyspnea, intolerance to heat, unexplained weight loss, diarrhea, fine tremors, hyperreflexia, tremulousness, palpitations and atrial fibrillation are seen in TF too. [symptoma.com]

  Symptoms of hyperthyroidism include heat intolerance, irritability, weight loss, frequent bowel movements, proximal muscle weakness, tremulousness, anxiety, fever, and fatigue. Menstruating females often suffer oligomenorrhea. [thebigl.co]

  Iodine is also used in preparation for subtotal thyroidectomy, in severe thyrocardiac disease, and in acute surgical emergencies Propranolol decreases tremulousness, palpitations, excessive sweating, eyelid retraction, and heart rate. [quizlet.com]

• Hand Tremor

  They may include Being nervous or irritable Mood swings Fatigue or muscle weakness Heat intolerance Trouble sleeping Hand tremors Rapid and irregular heartbeat Frequent bowel movements or diarrhea Weight loss Goiter, which is an enlarged thyroid that [icdlist.com]

• Fine Tremor

  Features of thyrotoxicosis like anxiety, hyperactivity, increased perspiration, dyspnea, intolerance to heat, unexplained weight loss, diarrhea, fine tremors, hyperreflexia, tremulousness, palpitations and atrial fibrillation are seen in TF too. [symptoma.com]

  She had mild tachycardia (112 beats/minute) and fine tremor of the hands. She had no thyroid enlargement, thyroid bruits, eye signs or pretibial myxedema. [cmaj.ca]

  • A fine tremor, muscle wasting, and proximal muscle group weakness with hyperactive tendon reflexes often are present. • The thyroid usually is diffusely and symmetrically enlarged, as evidenced by an enlarged pyramidal lobe. • Overlying bruit or thrill [slideshare.net]

The initial diagnosis of TF is based on clinical suspicion. A detailed history is essential to determine medicine intake, diet, the degree of symptom progression and underlying psychiatric issues. Physical examination should take into consideration the patient's heart rate, basal metabolic rate, presence or absence of goiter, exophthalmos, and myxedema. Laboratory biochemical tests are required to determine total triiodothyronine (T3), total thyroxine (T4), thyroid-stimulating hormone (TSH), TSH receptor, and thyroglobulin level. An elevated free thyroxine index (ratio of T-4 to T-3) [5], diminished thyroglobulin level [6] with an increased basal metabolic rate are diagnostic of TF. Patients with a positive TSH receptor and hyperthyroidism can be misdiagnosed as Grave's disease [7]. To distinguish TF from other causes of thyrotoxicosis, fecal thyroxine levels can be obtained with elevated levels confirming the diagnosis of TF [8].

An imaging study like color doppler ultrasonography is also useful to diagnose TF as it demonstrates the lack of thyroid blood flow [9]. If a patient has an elevated free thyroid hormone level with low TSH levels but is not able to provide a history of ingesting thyroid hormones, a radioactive iodine I-123 uptake is indicated and a low uptake is suggestive of TF [10].

A psychiatrist referral must be considered to exclude Munchausen syndrome [11] and other psychiatric disorders.

• Mediastinal Shift

  Chest X-ray showed mixed interstitial and alveolar opacities within the mid and upper lung zones, more on the left side with no cardiomegaly or mediastinal shifting. [tandfonline.com]

• Left Axis Deviation

  Normal sinus rhythm, left axis deviation, no abnotmality. The white blood count was 6,850 cells per c. mm. 15.5 Gm. per cent. Erythrocyte sedimentation rate was 10 mm. per hour (Westegren). [kundoc.com]

• Increased Basal Metabolic Rate

  An elevated free thyroxine index (ratio of T-4 to T-3), diminished thyroglobulin level with an increased basal metabolic rate are diagnostic of TF. Patients with a positive TSH receptor and hyperthyroidism can be misdiagnosed as Grave's disease. [symptoma.com]

  basal metabolic rate and tissue thermogenesis. [statpearls.com]

  ACTIONS OF THYROID HORMONE • Increases oxygen consumption • Increases carbohydrate and lipid catabolism • Stimulates protein synthesis • Increases basal metabolic rate • Increases thermogenesis • Increases expression of the low-density lipoprotein (LDL [quizlet.com]

• Early Repolarization

  Thyroxine causes early repolarization changes and also increases coronary vascular spasm. A study conducted on 403 patients with various kinds of hyperthyroidism evaluated the types of arrhythmias [16]. [ncbi.nlm.nih.gov]

• Brain Edema

  It was not considered safe by the neurologists to bring her serum sodium level down quickly, as it could worsen her brain edema. [tandfonline.com]

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6. Mariotti S, Martino E, Cupini C, et al. Low serum thyroglobulin as a clue to the diagnosis of thyrotoxicosis factitia. N Engl J Med. 1982;307:410–412.
7. Jahagirdar VR, Strouhal P, Holder G, Gama R, Singh BM. Thyrotoxicosis factitia masquerading as recurrent Graves’ disease: Endogenous antibody immunoassay interference, a pitfall for the unwary. Ann Clin Biochem. 2008; 45: 325-7
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10. Braverman LE. Evaluation of thyroid status in patients with thyrotoxicosis. Clin Chem. 1996;42:174–178
11. Mittra ES, Niederkohr RD, Rodriguez C, et al. Uncommon causes of thyrotoxicosis. J Nucl Med 2008; 49:265-278