THYROID DISORDERS

Question 1

*Meds that cause hypothyroidism

Answer 1

Decreased TSH (dopamine, glucocorticoids, somatostatin
Decreased thyroid hormone synthesis (lithium, methimazole, PTU, amiodarone)
Decreased thyroid hormone secretion (iodide, lithium, amiodarone, thalidomide)

Question 2

*Meds that cause hyperthyroidism

Answer 2

iodide
lithium
amiodarone

Question 3

Which med can cause hypothyroidism and hyperthyroidism?

Answer 3

amiodarone (37% iodine)

Question 4

*Hypothyroidism - DOC

Answer 4

Levothyroxine (Synthroid)

Question 5

*Levothyroxine - DDI (decreased absorption)

Answer 5

cholestyramine 
Ca carbonate
sucralfate
ALOH, FeSO4
Fiber

Question 6

*Levothyroxine - DDI (increased clearance)

Answer 6

rifampin

carbamazepine/phenobarb/phenytoin (4

Question 7

*Why is hypothyroidism treated differently in pregnancy?

Answer 7

Needs higher dose (+45% or 36mcg/d) because estrogen increases TGB so decreases TSH
Organogenesis is 8-10 wks so get dose changed early
DOC still Levothyroxine

Question 8

*Hyperthyroidism - preferred treatment

Answer 8

surgery (after 6-8 wks of PTU to calm down thyroid)
iodine to decrease vascularity
propranolol to maintain pulse
+/- levothyroxine

Question 9

*Hyperthyroidism - treatment options

Answer 9

surgery
antithyroid meds:
thionamides (PTU or MMI)
iodides (SSKI or Potassium iodide)
Adrenergic blockers (propranol and nadolol)
Radioactive sodium iodide 131 (RAI)

Question 10

How long after RAI does hypothyroidism occur?

Answer 10

3-12 months

can repeat dose at 6 months if still hyperthyroid