Thyroid Drugs

Question 1

Can be used to suppress TSH from benign nodules or multinodular goiters, hasimoto’s, and TSH thyroid carcinoma

Answer 1

Levothyroxine T4

Question 2

Given IV for myxedema coma in life threatening situation. Severe hypothyroidism needing immediate effect

Answer 2

Levothyroxine T4

Question 3

Must be careful with drugs that reduce thyroxine bioavailability (stagger dosing to reduce interaction) - calcium carbonate, aluminum hydroxide, cholestyramine, colesevelam

Answer 3

Levothyroxine T4

Question 4

If a woman is taking oral contraceptives you should __________ dose of T4

Answer 4

Increase b/c estrogen increases serum thyroid binding globulin

Question 5

If woman stops taking oral contraceptives you should ______ dose of T4

Answer 5

Decrease

Question 6

Glucocorticoids (anabolic steroids) __________ serum thyroid binding globulin

Answer 6

Decrease

Question 7

Propylthiouracil and amiodarone inhibit

Answer 7

5’ deiodinase

Question 8

Addition of thyroxine (levothyroxine T4) _________ anticoagulant activity of warfarin. Monitor INR values

Answer 8

Increases

Question 9

Can cause palpitations, tachycardia, and increased BP

Answer 9

Levothyroxine T4

Question 10

Levothyroxine T4 is main drug used to treat

Answer 10

Hypothyroidism

Question 11

Propylthiouracil and methimazole

Answer 11

Anti thyroid agents (thionamides)

Question 12

Using iodine to suppress thyroid hormone synthesis is contraindicated in

Answer 12

Pregnancy

Question 13

Inhibit iodide incorporation into tyrosine residues and inhibit iodotyrosyl coupling to form iodothyronine

Answer 13

Anti-thyroid agents (propylthiouracil and methimazole)

Question 14

Inhibits peripheral 5’-deiodinase (D1)

Answer 14

Propylthiouracil

Question 15

Anti-thyroid agents propylthiouracil and methimazole are used for

Answer 15

Hyperthyroidism

Question 16

Used for pre surgical treatment prior to thyroidectomy

Answer 16

Anti-thyroid agents (propylthiouracil and methimazole)

Question 17

Preferred antithyroid drug during pregnancy

Answer 17

Propylthiouracil

Question 18

Methimazole has ________ t1/2 compared to propylthiouracil

Answer 18

Longer

Question 19

Can cause agranulocytosis and aplastic anemia

Answer 19

Methimazole

Question 20

Can cause hepatic necrosis and nephritis. Liver injury and failure

Answer 20

Propylthiouracil

Question 21

Used in hyperthyroidism, thyroid carcinoma, graves. Can induce hypothyroidism by causing damage to thyroid follicular cells

Answer 21

Iodine 131

Question 22

Used preoperatively to reduce vascularity of thyroid before surgery. Used to block radioiododine uptake with nuclear power plant accident

Answer 22

Iodide

Question 23

Not used in pregnancy because it crosses the placenta

Answer 23

Iodide

Question 24

Can induce goiter, suppress thyroid function in fetus, induce hypothyroidism

Answer 24

Iodide