Thyroid Drugs

Question 1

This pertains to the inhibition of iodine organification due to large doses of iodine

Answer 1

Wolff-Chaikoff block

Question 2

This is the preparation of choice for thyroid replacement and suppression therapy because of its stability, content uniformity, low cost, lack of allergenic foreign protein, easy laboratory measurement of serum levels, and long half-life.

Answer 2

Synthetic levothyroxine

Question 3

This thyroid preparation is three to four times more portent than levothyroxine, but is not recommended for routine replacement therapy.

Answer 3

liothyronine (T3)

Question 4

T3 should be avoided in patients with what disease?

Answer 4

cardiac disease

Question 5

These are agents that suppress secretion of T3 and T4 to subnormal levels and thereby increase TSH, which in turn produces glandular enlargement

Answer 5

Goitrogens

Question 6

Give 3 thioamides

Answer 6

methimazole
propylthiouracil
carbimazole (in the UK)

Question 7

This is the drug of choice for hyperthyroidism in children and adults

Answer 7

Methimazole

Question 8

This drug is reserved for use during the first trimester of pregnancy, in thyroid storm, and in those experiencing adverse reactions to methimazole.

Answer 8

propylthiouracil

Question 9

Black box warning for PTU

Answer 9

severe hepatitis

Question 10

Most common adverse effect of thioamides

Answer 10

maculopapular pruritic rash (sometimes with fever)

Question 11

Among the thioamides, which drug commonly manifests with cholestatic jaundice?

Answer 11

methimazole

Question 12

The most dangerous complication of thioamides (methimazole)

Answer 12

agranulocytosis

Question 13

These agents may hasten recovery of granulocytes affected with the use of thioamides.

Answer 13

Colony-stimulating factors

Question 14

Give the monovalent anions that can block uptake of iodide by the thyroid gland through competitive inhibition of its transport mechanism

Answer 14

perchlorate
pertechnetate
thiocyanate

Question 15

The major clinical use of this drug is to block thyroidal reuptake of I− in patients with iodide-induced hyperthyroidism (e.g., amiodarone-induced hyperthyroidism).

Answer 15

potassium perchlorate

Question 16

Despite its ability to address amiodarone-induced hyperthyroidism, potassium perchlorate is rarely used due to its association with what condition?

Answer 16

aplastic anemia

Question 17

This pertains to the phenomenon of hyperthyroidism induction with iodide use

Answer 17

Jod-Basedow phenomenon

Question 18

These major antithyroid agents inhibit organification and hormone release and decrease the size and vascularity of the hyperplastic gland.

Answer 18

Iodides

Question 19

The pharmacologic dose of iodides

Answer 19

> 6mg/d

Question 20

The major action of iodides is to inhibit hormone release, possibly through inhibition of:

Answer 20

thyroglobulin proteolysis

Question 21

This is given preoperatively to hyperthyroid patients to limit intraoperative bleeding and related complications resulting from thyroid gland vascularization.

Answer 21

Lugol’s solution (potassium iodide)

Iodides decrease the vascularity size, and fragility of a hyperplastic gland, making the drugs valuable as preoperative preparation for surgery.

Question 22

In radiation emergencies involving release of radioactive iodine isotopes, the thyroid-blocking effects of _________ can protect the gland from subsequent damage if administered before radiation exposure.

Answer 22

potassium iodide

Question 23

This is the only isotope used for treatment of thyrotoxicosis (Others are used in diagnosis.)

Answer 23

131 I

Administered orally in solution as sodium 131I

Question 24

This has been the β blocker most widely studied and used in the therapy of thyrotoxicosis.

Answer 24

Propranolol

Propranolol at doses greater than 160 mg/d may also reduce T3 levels approximately 20% by inhibiting the peripheral conversion of T4 to T3.

Question 25

Chronic overtreatment with T4, particularly in elderly patients, can increase the risk of which cardiac and skeletal conditions?

Answer 25

atrial fibrillation
accelerated osteoporosis

Question 26

This is the end state of untreated hypothyroidism

Answer 26

Myxedema coma

Question 27

Treatment of choice for myxedema coma

Answer 27

intravenous levothyroxine

Question 28

Intravenous ___________ is indicated if the patient with myxedema coma has associated adrenal or pituitary insufficiency but is probably not necessary in most patients with primary myxedema.

Answer 28

hydrocortisone

Question 29

Give 2 conditions in which PTU is preferred over Methimazole

Answer 29

pregnancy and thyroid storm

Question 30

During acute phase thyrotoxicosis, which β-adrenoceptor–blocking agents will control tachycardia, hypertension, and atrial fibrillation (give 2)

Answer 30

propranolol and metoprolol

Question 31

This drug, given at 90–120 mg three or four times daily, can be used to control tachycardia in patients in whom β blockers are contraindicated, e.g., those with asthma.

Answer 31

Diltiazem

Question 32

These agents can rapidly lower T4 levels by increasing the fecal excretion of T4.

Answer 32

Bile acid sequestrants (e.g., cholestyramine)

Question 33

Pharmacologic therapy for severe, acute inflammatory reaction with ophthalmopathy in Grave’s disease

Answer 33

prednisone

Question 34

The is a fully human monoclonal antibody that targets the insulin-like growth factor 1 (IGF-1) receptor (IGF-1R), approved for the treatment of thyroid eye disease

Answer 34

Teprotumumab

Question 35

2 types of amiodarone thyrotoxicosis

Answer 35

iodine-induced (type I)
inflammatory thyroiditis (type II)

Question 36

Treatment for type I amiodarone-induced thyrotoxicosis

Answer 36

thioamides

Question 37

Treatment for type I amiodarone-induced thyrotoxicosis

Answer 37

glucocorticoids

Question 38

Most common cause of nontoxic goiter worldwide is:

Answer 38

iodine deficiency