Thyroid and Anti-Thyroid Hormones

Question 1

Treatment of Hypothyroidism

Answer 1

Requires hormone replacement

Increase T4, normalize TSH, relieve symptoms

Question 2

Hypothyroidism drugs

Answer 2

Levothryoxine - T4 **
Liothyronin - T3
Liotrix - T3/T4

Question 3

AE Hypothyroidism drugs

Answer 3

Hyperthyroidism symptoms

Special consideration with CAD - low thyroid protective; treatment could provoke MI/arrhythmia

Question 4

MOA Hyperthyroidism drugs

Answer 4

Inhibit peroxidase, iodine organification and coupling of iodotyrosines
Concentrate in thyroid = low SE

Question 5

AE Methimazole

Answer 5

altered taste/smell

Question 6

AE Propylthiouracil

Answer 6

severe fatal hepatitis

Question 7

MOA Iodides for Hyperthyroidism

Answer 7

inhibit hormone release by inhibiting proteolysis of Tgb

High dose can inhibit organifcation step

Question 8

KI, Lugol’s Solution

Answer 8

increases intraglandular iodide delaying onset of thioamide therapy
Withdrawal will produce thyrotoxicosis
Flu-like symptoms

Question 9

Radioactive Iodine

Answer 9

B-rays - destroy parenchymal cells of thyroid
Y-rays pass through - detect concentration of RAI
AE - hypothyroidism, contraindicated in pregnancy

Question 10

Anion inhibitors

Answer 10

Perchlorate, pertechnetate, thiocyanate
not used: can treat iodide-induced hyperthyroidism
AE - aplastic anemia

Question 11

Propranolol as adjunct

Answer 11

control tachycardia, HTN, A-fib, thyroid storm
Antagoniszes B1/B2; also inhibits conversion of T4 to T3
AE - asthma, AV block, hypotension, bradycardia

Question 12

Other adjuncts

Answer 12

Diltiazem - tachycardia w/asthma

Barbiturates - increase T4 metabolism