Thyroid Disorders

1 . Which of the following statements regarding thyroid hormones is false? 

A – T4 is more potent than T3

B – T4 has a shorter half – life

C – T4 is converted into T3 

D – The thyroid gland primarily produces T4

E – Both T3 and T4 are highly protein bound 

 

2. Which of the following accurately depicts the levels of thyroid hormones in hypothyroidism? 

A – Low T4, high TSH, 

B – Low T4, low TSH

C – High T4, high TSH

D – High T4, low TSH

E – None of the above 

 

3. Which of the following is NOT a symptom of hypothyroidism?

A – Constipation 

B – Weight loss 

C – Depression 

D – Dry skin 

E – Loss of hair 

 

4. Which of the following is a sign of hypothyroidism? 

A – Tachycardia

B – Irritability 

C – Diarrhea

D – Cold intolerance 

E – Insomnia 

 

5. Which of the following accurately depicts the levels of thyroid hormones in hyperthyroidism? 

A – Low T4, high TSH, 

B – Low T4, low TSH

C – High T4, high TSH

D – High T4, low TSH

E – None of the above 

 

6. Which of the following drugs may cause hypothyroidism? 

A – Norethindrone 

B – Nefazodone

C – Lithium

D – Rifampin

E – Lamotrigine 

 

7. Which of the following is the most common cause of hypothyroidism?

A – Graves disease

B – Hashimoto’s disease 

C – Myxedema coma

D – Pituitary failure 

E – Radiation 

 

8. What is the IV to PO ratio of levothyroxine? 

A – 1 : 1.5

B – 1 : 2.5

C – 0.75 : 1

D – 0.5 : 1

E – 1 : 1 

 

9. What is the recommended daily dose of levothyroxine? 

A – 1.5 mcg/kg/day

B – 1.6 mcg/kg/day

C – 2.0 mcg/kg/day

D – 2.5 mcg/kg/day

E – 3.0 mcg/kg/day

 

10. MJ is a 55 year old female diagnosed with hypothyroidism. PMH: hypertension, hyperlipidemia, celiac disease, CAD s/p DES

        Home medications: lisinopril 20mg daily, atorvastatin 40mg daily, aspirin 81mg daily, metoprolol 100mg daily. 

        Which of the following is the most appropriate starting dose for MJ? 

A – Levothyroxine 12 mg 

B – Levothyroxine 25 mcg 

C – Levothyroxine 50 mg

D – Levothyroxine 75  mcg 

E – Levothyroxine 100 mg 

 

11. Patient is prescribed levothyroxine 50 mcg daily. What is an important counseling point regarding this medication? 

A – Take this medication at bedtime

B – Take this medication with the evening meal 

C – Take this medication on an empty stomach 30- 60 minutes before breakfast or 3 hours after dinner (at bedtime) 

D – Take this medication with breakfast 

E – None of the above 

 

12. TJ is a 55 year old male diagnosed with hypothyroidism. PMH: hypertension, hyperlipidemia, celiac disease,

         Home medications: lisinopril 20mg daily, atorvastatin 40mg daily, Ferrous sulfate 325mg BID.  Allergies: Dye, gluten 

         TJ is started on levothyroxine 50 mcg to treat his hypothyroidism. Choose the correct statement. 

A – Take ferrous sulfate 4 hours apart from levothyroxine

B – TJ has a dye allergy and levothyroxine is contraindicated

C – Levothyroxine may increase levels of atorvastatin 

D – Take lisinopril 4 hours apart from levothyroxine 

E – None of the above 

 

13. Which of the following is a warning associated with thyroid replacement therapy? 

A – Drug-induced lupus erythematosus

B – Neutropenia

C – Angioedema

D – Hypocalcemia

E – Decreased bone mineral density 

 

14. CJ is a 55 year old male diagnosed with hypothyroidism. PMH: hypertension, hyperlipidemia, Atrial fibrillation

         Home medications: lisinopril 20mg daily, atorvastatin 40mg daily, metoprolol 100mg daily, warfarin 5mg MWF and 7mg TueThursSatSun

         CJ is started on liothyronine 25 mcg daily. Before verifying this medication, you notice that the patient is also on warfarin. What is the most appropriate course of action? 

A – Warfarin and liothyronine do not interact, it is okay to verify 

B – Thyroid hormones will increase the INR, warfarin dose should be decreased

C – Thyroid hormones will decrease the INR, warfarin dose should be increased 

D – Thyroid hormones will increase the INR, warfarin dose should be increased

E – Thyroid hormones will decrease the INR, warfarin dose should be decreased 

 

15. Which of the following statements is true regarding thyroid replacement therapy? 

A – Levothyroxine is the synthetic form of thyroid hormone T3 

B – Estrogen increases thyroid hormone levels 

C – Thyroid USP contains both T3 and T4 

D – An advantage to using liothyronine is its long half-life 

E – With increased age, patients often require higher doses of thyroid hormones 

 

16. Which of the following is the preferred medication for treating hyperthyroidism in the 1st trimester of pregnancy? 

A – Methimazole

B – Iodides

C – Propranolol

D – Propylthiouracil

E – Liothyronine

 

17. Which of the following is true regarding pregnancy and thyroid disorders? 

A – Liothyronine is the recommended agent for treating hypothyroidism in pregnancy 

B – Pregnant women require higher doses of thyroid hormones

C – Methimazole is safe to use in the 1st trimester of pregnancy 

D – Due to to the toxic nature of the drugs, surgery is recommended for treating hyperthyroidism in pregnancy

E – None of the above 

 

18. Which of the following is a common side effect of lugol’s solution? 

A – Sore throat

B – Metallic taste

C – GI upset

D – Hives

E – All of the above 

 

19. Which of the drugs is correctly paired with its mechanism of action? 

A – *SSKI: temporarily inhibits the secretion of thyroid hormones

B – Propranolol: Inhibits the peripheral conversion of T4 to T3

C – Lugol’s solution: Inhibits the synthesis of thyroid hormones by blocking the oxidation of iodine in the thyroid gland

D – Methimazole: beta agonist that inhibits the symptoms of hyperthyroidism 

E – None of the above 

*SSKI: saturated solution of potassium iodide 

 

20. RJ is a 65 year old male who presented to the ER with fever, tachycardia, profuse sweating and delirium. He had not been taking his medication for hyperthyroidism which led to a thyroid storm. Which of the following is the most appropriate for the management of thyroid storm? 

A – Methimazole, prednisone and supportive care

B – PTU, SSKI, propranolol, hydrocortisone, and supportive care 

C – Radiation, propranolol, prednisone, and supportive care

D – Surgery, dexamethasone and supportive care

E – PTU, methimazole, methylprednisolone and supportive care

 

Answer Key

1. A – T3 is the more active form  
2. A – hypothyroidism results in low levels of T4 which signals the hypothalamus to secrete more TRH which then stimulates the pituitary gland to produce TSH. TSH acts on the thyroid gland to produce more thyroid hormones (primarily T4) 
3. B – Hypothyroidism is associated with slowing down of the body and low metabolism which leads to weight gain, fatigue, depression etc. 
4. D 
5. A – Hyperthyroidism results in high levels of T4 which inhibits the secretion of TRH and TSH through negative feedback loop. 
6. C – Key drugs that may cause hypothyroidism include: amiodarone, lithium, carbamazepine, interferons and tyrosine kinase inhibitors 
7. B – Hashimoto’s disease is the most common cause of hypothyroidism. It is an auto-immune disorder in which the patient’s own antibodies attack the thyroid gland. 
8. C
9. B
10. B – If pre-existing coronary artery disease, the starting dose is 12.5- 25 mcg/day
11. C – Levothyroxine should be taken on an empty stomach 30-60 minutes before breakfast or 3 hours after dinner, at bedtime 
12. A – levothyroxine should be taken 4 hours apart from antacids, iron, calcium supplements. If a patient has a dye allergy, 50 mcg tablet is white and has no dye and is safe to use 
13. E – thyroid replacement therapy is associated with decreased bone mineral density which may lead to osteoporosis. Risk is increased with dose, age and gender 
14. B – Thyroid replacement therapy increases effects of anticoagulants, INR will go up and warfarin dose should be lowered 
15. C – Thyroid USp contains both T3 and T4. 
16. D – Propylthiouracil is preferred in the 1st trimester; Methimazole is often recommended in the 2nd and 3rd trimester 
17. B
18. E
19. A
20. B