Thyroid-Hyperthyroid Flashcards
(39 cards)
Thyroid
Hormone secretion T3, T4
has to uptake iodine, produce thyroglobulin
Thyroid Hormone Function
growth & development maintenance metabolism temp homeostasis heart rate
Normal levels Free T4
.8-2.7 ng/dL
Normal Free T3
230-420 pg/dL
Normal TSH
.404 mIU/L
Drugs that increase TGB, therefore decreasing free thyroid hormone levels
Estrogen tamoxifen heroin methadone mitotane fluorouracil
Drugs that decrease TGB therefore increasing free thyroid hormone levels
Androgens
anabolic steroids
slow release nicotinic acid
glucocorticoids
Drugs decreasing secretion of TSH
dopamine
glucocorticoids
octreotide
Drugs that decrease thyroid hormone secretion
lithium
iodide & iodine preparations
radiocontrast dyes
amiodarone (can increase or decrease because its 37% iodine and it stays in your system for a year)
Dx criteria for Hyperthyroidism
lows TSH
elevated free T3/T4
Increased radioactive iodine uptake
Treatments for Hyperthyroidism
anti-thyroid meds
radioactive iodine
thyroidectomy
symptomatic tx (B-blockers)
Anti-thyroid drugs
possible remission
low cure rate (40-50%)
can have ADR’s
1st line in children and pregnant
Radioactive Iodine
curative
will prob become HYPOthyroid and need meds for life (l-thyroxine)
best for people with goiter
Surgery
rapid effect, useful if you have to Bx anyway
First Line Anti-thyroid (Thioamides)
Methimazole
PTU if someone is in thyroid storm or 1st trimester
Predictors of remission on Thioamides
small goiter
mild dz
low or negative thyroreceptor antibody titer
Thioamide MOA
inhibits thyroid hormone synthesis (blocks incorporation of iodine into hormone)
PTU–>also inhibits peripheral T4–>T3 conversion within hours
depletion of stored hormone & prevention of new hormone synthesis
Absorption of Thioamides
in Gi tract
reach peak level in 1 hour
Distribution of Thioamide
concentrated in the thyroid
PTU–> 80% protein binding
half life is 2-3 houra
Metabolism of Thioamide
Liver
Elimination of Thioamide
renal (eliminated as metabolites)
Methimazole 1/2 life= 5-13 hrs
PTU 1/2 life= 1-2 hrs
Common Adverse Effects of Thioamides
GI upset
arthralgia
rash, urticaria, pruritis
Agranulocytosis
serious adverse effect of Thioamide
more likely to occure in higher doese, and with older paptients
0.2-.05%
S&S= fever, sore throat, bleeding, brusing, malaise, stomatitis
Hepatotoxicity
Serious adverse affect of thioamide
higher risk in PTU
should do LFT’s, if high d/c
S&S–> ligth colored stool, dark urine, yellowing of the skin and eyes