Approximately 20 million Americans have some type of thyroid disease, and more than 12% of the US population will develop a thyroid disorder in their lifetime.1 Can you identify these medications for the treatment of hypothyroidism, hyperthyroidism, and thyroid eye disease? To find out, match each brand name in Section I with its generic name in Section II.

Section I.

______ 1. Synthroid (AbbVie Inc.)

______ 2. Tapazole (Pfizer Inc.)

______ 3. Tepezza (Horizon Therapeutics Ireland DAC)

Section II

a. methimazole. This drug inhibits thyroid hormone synthesis. It is administered orally one to three times per day, with the daily dose depending on the severity of hyperthyroidism. Dosing is adjusted according to levels of thyroid-stimulating hormone and free thyroxine (T4), which should be monitored. T4 is a thyroid hormone. Several important safety warnings related to the use of methimazole should be considered. First, its use in the first trimester of pregnancy may be associated with fetal harm, so patients should be warned of the potential risks. An alternative agent must be considered. There is also the risk of agranulocytosis. Patients should be counseled to immediately report symptoms of sore throat or fever, which may be signs of this condition. Hepatotoxicity, including hepatic dysfunction and hepatocellular injury, may occur. Evaluation of liver function is warranted in patients with symptoms consistent with liver injury, such as pruritus.2

b. teprotumumab-trbw. This injectable drug is an insulin-like growth factor-1 receptor blocker indicated for the treatment of thyroid eye disease. After reconstitution and dilution, it is administered as an initial 10 mg/kg I.V. infusion, followed by 20 mg/kg every 3 weeks for seven additional infusions. The first two infusions should be administered over 90 minutes, with the ability to reduce the infusion time to 60 minutes if tolerated. Infusion reactions, such as transient BP elevations, feeling hot, tachycardia, dyspnea, headache, and muscular pain, have been reported during administration. If this occurs, slowing or interrupting the infusion and providing appropriate medical treatment is indicated. Patients with existing inflammatory bowel disease may experience a disease flare; discontinuation of teprotumumab-trbw should be considered. Glucose level monitoring is warranted, as hyperglycemia may occur. The most common adverse reactions include muscle spasms, nausea, alopecia, diarrhea, fatigue, hyperglycemia, hearing impairment, dry skin, dysgeusia, and headache.3

c. levothyroxine. Also known as synthetic T4, this drug is indicated for the treatment of hypothyroidism. Dosing for this oral medication is based on a patient's body weight, with consideration for age and the presence of underlying cardiovascular disease. It should be administered at the same time each day, preferably on an empty stomach at least 30 to 60 minutes before breakfast and with administration separated by 4 hours from other medications that may interfere with absorption such as calcium, iron, magnesium, and sevelamer. Most importantly, thyroid hormone supplements should not be used as treatments for obesity or to promote weight loss as serious or life-threatening toxicities may occur.4

Answers: 1. C, 2. A, 3. B

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