Thyroid-Hyperthyroid

Question 1

Thyroid

Answer 1

Hormone secretion T3, T4

has to uptake iodine, produce thyroglobulin

Question 2

Thyroid Hormone Function

Answer 2

growth & development
maintenance 
metabolism
temp homeostasis
heart rate

Question 3

Normal levels Free T4

Answer 3

.8-2.7 ng/dL

Question 4

Normal Free T3

Answer 4

230-420 pg/dL

Question 5

Normal TSH

Answer 5

.404 mIU/L

Question 6

Drugs that increase TGB, therefore decreasing free thyroid hormone levels

Answer 6

Estrogen
tamoxifen
heroin
methadone
mitotane
fluorouracil

Question 7

Drugs that decrease TGB therefore increasing free thyroid hormone levels

Answer 7

Androgens
anabolic steroids
slow release nicotinic acid
glucocorticoids

Question 8

Drugs decreasing secretion of TSH

Answer 8

dopamine
glucocorticoids
octreotide

Question 9

Drugs that decrease thyroid hormone secretion

Answer 9

lithium
iodide & iodine preparations
radiocontrast dyes
amiodarone (can increase or decrease because its 37% iodine and it stays in your system for a year)

Question 10

Dx criteria for Hyperthyroidism

Answer 10

lows TSH
elevated free T3/T4
Increased radioactive iodine uptake

Question 11

Treatments for Hyperthyroidism

Answer 11

anti-thyroid meds
radioactive iodine
thyroidectomy
symptomatic tx (B-blockers)

Question 12

Anti-thyroid drugs

Answer 12

possible remission
low cure rate (40-50%)
can have ADR’s
1st line in children and pregnant

Question 13

Radioactive Iodine

Answer 13

curative
will prob become HYPOthyroid and need meds for life (l-thyroxine)
best for people with goiter

Question 14

Surgery

Answer 14

rapid effect, useful if you have to Bx anyway

Question 15

First Line Anti-thyroid (Thioamides)

Answer 15

Methimazole

PTU if someone is in thyroid storm or 1st trimester

Question 16

Predictors of remission on Thioamides

Answer 16

small goiter
mild dz
low or negative thyroreceptor antibody titer

Question 17

Thioamide MOA

Answer 17

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

Question 18

Absorption of Thioamides

Answer 18

in Gi tract

reach peak level in 1 hour

Question 19

Distribution of Thioamide

Answer 19

concentrated in the thyroid
PTU–> 80% protein binding
half life is 2-3 houra

Question 20

Metabolism of Thioamide

Answer 20

Liver

Question 21

Elimination of Thioamide

Answer 21

renal (eliminated as metabolites)
Methimazole 1/2 life= 5-13 hrs
PTU 1/2 life= 1-2 hrs

Question 22

Common Adverse Effects of Thioamides

Answer 22

GI upset
arthralgia
rash, urticaria, pruritis

Question 23

Agranulocytosis

Answer 23

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

Question 24

Hepatotoxicity

Answer 24

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

Question 25

Monitoring Free T4 Levels

Answer 25

4 mo after initiation of therapy

every 4-8 wks until normal–> then every 2-3 months

Question 26

LFT’s

Answer 26

when pt is having symptoms (jaundice, joint pain, abd pain, light stoll, dark urine, GI upset, fatigue

Question 27

MOA of Iodides

Answer 27

Inhibits thyroid hormone release
decrease thyroid release
decrease vascularity of thyroid gland –> for pre-op

symptoms improve within a week

Question 28

Uses of Iodides w/Thyroid dz

Answer 28

pre-op (reduce vasculatiry)
Thyrotoxic crisis–>decrease iodine accumulation
prevents thyroid uptake of radioactive iodine

Question 29

Adverse affects of Iodide

Answer 29

rash
gi upset
paresthesia
immune hypersensitivity rxns
salivary gland swelling

Overdose–>burning in mouth, metallic taste, sore teeth, cold sx

Question 30

Beta Blocker use in Hyperthyroidism

Answer 30

Tx’s Symptoms (palps, tachy, tremor, heat intolerance)
used esp if pt;s resting HR is over 90 and thy are elderlu, postpartum, or child

can also be used in thyroidstorm (to decrease their HR)

Question 31

Beta Blockers MOA

Answer 31

block B adrenergic receptors–>mitigates symptoms of thyrotoxicosis

Propranolol and nadolol can decrease conversion of T4 to T3

Question 32

Radioactive Iodine (RAI) MOA

Answer 32

disrupts hormone synthesis, incorporites itself into the thyroid hormone, and thyroglobulin

Works in a couple weeks–>follicles begin to necrose

can be in a person’s system for up to a month (because its half life is 5 days

contraindicated in pregnany, breast feeding, thyroid CA

Question 33

Indications of RAI

Answer 33

ablation for graves

pt’s with surgical risk

Question 34

Benefits of RAI

Answer 34

well tolerated, low risk thyroid storm

Question 35

What to monitor with RAI

Answer 35

T3/T4: 1-2 mo’s after treatment (hypothyroidism usually occurs 4 weeks after tx)

Question 36

Adverse Effects in RAI

Answer 36

dysphagia, thyroid tenderness

Question 37

Tx of Thyroid storm

Answer 37

PTU–> med of choice (prevents T4–>T3 conversion)

SSKI–> blocks new hormone

Hydocortisone–> blocks T4 conversion

Beta Blocker–> propranolol (blocks T4 conversion)
Esmolol infusion when po isnt possible

Corticosteroid (dexamethasone) to stabilize BP

Question 38

Subclinical Hyperthyroidism

Answer 38

low TSH but normal levels of thyroid hormone (T3/T4)

can cause A-Fib (and increasing risk for strokes)

Question 39

Tx of Subclinical Hyperthyroidism

Answer 39

If its caused by amiodarone tx with methimazole (type 1) or glucocorticoids (type 2) or both.

if not from amiodarone–. usually dont tx, monitor hr and TSH