Thyroid and Antithyroid drug list

Question 1

L-T4

Answer 1

Levothyroxine

Question 2

L-T3

Answer 2

liothyronine sodium

Question 3

mixture of L-T3 and L-T4

Answer 3

liotrix

Question 4

What are the anti-thryoid drugs?

Answer 4

propylthiouracil, methimazole, carbimazole

Question 5

3 proteins that bind T3 and T4

Answer 5

albumin, TBG, TBPA

Question 6

What happens to the ratio of T4:T3 in iodine deficiency?

Answer 6

Goes from 4:1 to 1:3

Question 7

T or F. IN the first trimester of pregnancy, the fetus relies on TH from maternal circulation.

Answer 7

T

Question 8

How are T3 and T4 metabolized

Answer 8

in liver through glucuronide and sulfate conjugation. Enterohepatic circulation

Question 9

____ transports T4 in CSF.

Answer 9

TTR

Question 10

Describe the binding of TBG

Answer 10

The major carrier, T4 tighter.

Question 11

Describe the binding of TTR (TGBPA)

Answer 11

Gets higher affinity after binding first T4

Question 12

*Figure out what slide 50 means about “higher level in blood for TTR than TBG”

Answer 12

Because TTR has higher affinity (lower Ka)?

Question 13

Describe binding of albumin

Answer 13

Both T3 and T4

Question 14

What are immediated, later, and last effects of TSH

Answer 14

Immediate: increased secretion
Later: iodide uptake, hormone synthesis, proteolysis
Last: hypertrophy and hyperplasia

Question 15

____ is the preferred method of preventing iodine deficiency.

Answer 15

Iodized salt

Question 16

TH act primarily through binding ____ receptors.

Answer 16

nuclear

Question 17

MOA of T3 and T4 at nucleus

Answer 17

T3: regulates transcription. Binds TRB1 and 2, TRa1. Binds mitochondrial membrane and activates enzymes.
T4: can bind same receptors but not regulate transription

Question 18

What drugs are used in hyperthyroidism?

Answer 18

thioureylenes(methimazole, PTU), carbimazole,

Question 19

MOA of PTU

Answer 19

inhibits peripheral conversion of T4 to T3, inhibit iodine organification

Question 20

MOA of thioureylenes and carbimazole

Answer 20

inhibit iodine organification

Question 21

Describe methimazole

Answer 21

10x more potent than PTU, crosses placenta and gets concentrated in fetal thyroid

Question 22

What anti-thyroid drug is used in pregnant pt?

Answer 22

PTU- less placentral transfer and excretion in milk

Question 23

Adverse reactions to PTU

Answer 23

minimal, agranulocytosis, skin rash

Question 24

ADE of iodinated contrast medium

Answer 24

Euthyroid–> hyperthyroidism

Hyperthyroid–> thyroid storm

Question 25

What do large doses of iodine do?

Answer 25

block release of TH, tx thyroid storm, decrease size and vascularity of gland–> preop!

Question 26

What is radioactive iondine?

Answer 26

oral, concentrated in thryoid, B radiation will destroy parenchymal cells, no evidence of damage to other tissues,

Question 27

Who can use radioactive iodine?

Answer 27

adults >35, NOT in women of child bearing age