Thyroid Drugs

Front 1

What are the 3 major steps in thyroid hormone synthesis?

Back 1

1. trapping (transport of iodide into thyroid cells)

2. organification (iodination of tyrosine on thyroglobulin)

3. coupling (making MIT or DIT)

Front 2

What are the drug interactions that cause hypothyroidism?

Back 2

amiodarone--> inh deiodinase
lithium--> inh TH synthesis
phenytoin,carbamezapine, rifampin--> increase met of TH

Front 3

Levothyroxine:

CU, AR, Interactions

Back 3

CU: hypothyroidism

AR: few side effects

Interactions: increase catabolism of Vit K dependent factors (enhance the action of anticoagulants)

Front 4

PTU/Methimazole

MOA, CU, AR

Back 4

MOA: inh TPO

AR: skin rash, lupus like rxn, agranulocytosis, hepatitis

PTU is 1st choice in pregnant women and children with hypothyroidism

Front 5

Perchlorate, Pertechnate, Thiocyanate

MOA, CU, AR

Back 5

MOA: block uptake of iodide

CU: hyperthyroidism

AR: perchlorate--> fatal anaplastic anemia

Front 6

Iodides

CU

Back 6

give when someone has radioactive iodide treatment done

Front 7

Propanolol

CU

Back 7

treat symptoms of hyperthyroidism

Front 8

I-131

CU

Back 8

irradiate the thyroid for extreme cases of hyperthyroidism

DO NOT GIVE TO PREGNANT WOMEN

Front 9

What are the Sx of hyperthyroidism?

Back 9

warm, moist skin, heat intolerance, tremors, increased HR, SOB, increased BMR

Front 10

What are the Sx of hypothyroidism?

Back 10

pale, cool skin, decreased HR, hypoventilate, dec BMR, lethargic, periorbital puffiness, delayed DTRs

Front 11

What is the difference b/w I-123 uptake in thyroiditis and Graves?

Back 11

Thyroiditis--> no uptake

Graves--> diffuse uptake

Front 12

What are the possible explanations for a patient who is hypothyroid for many years and suddenly has a inc in TSH?

Back 12

1. other meds (change in weight)
2. switching brands
3. calcium or vit D supplements
4. estrogen or BC

Front 13

What is the significance of T3RU?

Back 13

high T3RU=hyperthyroidism
low T3Ru=hypothyroidism