Thyroid Disorders Flashcards
T__ is converted to T__ in the periphery
T4 is converted to T3 in periphery
T3 is more/less potent than T4
T3 is more potent than T4
T3 has a shorter/longer t 1/2 compared to T4
shorter
most common cause of hypothyroidism
Hashimotos where antibodies attack the thyroid gland and prevent thyroid hormone release
normal range for FT4 and TSH
TSH 0.3-3
FT4 0.9-2.3
at what age should providers consider thyroid screening
60
first line treatment for hypothyroidism? Dose?
levothyroxine 1.6mcg/kg/day (USE IBW)
why is levothyroxine (T4) preferred over NP thyroid and Armour Thyroid
fixed T4 concentrations
others are T3 and T4 with inconsistent amounts
patient MA 61 yo female reporting to PCP with the following thyroid panel and known CVD.
TSH 4.5 (normal 0.3-3)
FT4 0.17 (normal 0.9-2.3)
MD wants to start levothyroxine. What dose should she be initiated on?
Patient is 5’7” and 82kg
12.5-25mcg po daily
normal dosing is 1.6mcg/kg/day using IBW, however the patient has known CVD and should be initiated on a lower starting dose of 12.5-25mcg po daily.
patient MA is initiated on levothyroxine 25mcg po daily for hypothyroidism. When should follow-up monitoring be done?
every 4-6 weeks until euthyroid, then 4-6 months later then 1 year later
How should levothyroxine be taken
empty stomach with a glass of water 60 min before breakfast and other medications
which medications decrease levothyroxine absorption and should be taken 4 hours apart
antacids (Fe, ADEK, Ca)
sevelamer
sucralfate
cholestyramine
magnesium
estrogen, SSRIs and CYP inducers decrease/increase thyroid hormone levels
decrease
warfarin and levothyroxine DDI
levoth will increase warfarin efficacy and increase PT/INR
pneumonic for levothyroxine tablet colors
orangutans orange 25mcg
will white 50mcg
vomit violet 75mcg
on olive 88mcg
you yellow 100mcg
right rose 112mcg
before brown 125mcg
they turquoise 137mcg
become blue 150mcg
loud lilac 175mcg
proud pink 200mcg
giants green 300mcg
