thyroid drugs

Question 1

prevalence

Answer 1

1) 1/13 americans have thyroid disease

Question 2

goiter

Answer 2

1) enlargement of the gland

Question 3

thyroid cancer

Answer 3

malignant neoplasm

Question 4

solitary thyroid nodules

Answer 4

1) most are benign

Question 5

thyroiditis

Answer 5

1) autoimmune hashimotos and graves

Question 6

hypothyroidism

Answer 6

1) little thyroid hormones

Question 7

synthesis of T4 and T3

Answer 7

1) iodide transported to apical membrane of follicle
2) cells synthesize thyroglobulin
3) TG transported to colloid in follicle
4) exposed tyrosyls which are iodinated by TPO (organification)
5) TSH causes TG to get inside the cell (endocytosis)
6) proteolyzed in lysosomes
7) T3 and T4 released in bloodstream

Question 8

metabolism

Answer 8

1) T3 and T4 in blood are completely bound to TBG
2) in tissues, there is step up and step down de-iodination by D1, D2, D3
- step up: T4 -> T3 (increase potency)
- step down T4 -> T3

Question 9

T4

Answer 9

1) high in bloodstream
2) half life is 7 days

Question 10

T3

Answer 10

1) less secreted but more activated in tissue
2) half life 1 day
3) more potent than T4

Question 11

glucocorticoids

Answer 11

1) lipophilic and are passed into cytoplasm, binds receptors, carry to nucleus
2) complex binds to DNA
3) response of genes and proteins

Question 12

thyroid hormone receptors

Answer 12

1) TR- alpha 1
- cardiac and skeletal muscles
2) TR- beta 1
- brain, liver kidney
3) TR beta 2
- hypothalamus and pituitary

present practically in all cells

Question 13

effects of thyroid hormones in different tissues

Answer 13

1) liver
- homeostasis of glucose and lipids
2) hypothalmus
- control of feeding, behavior
3) skeletal muscle
- activity of skeletal and cardiac muscle
4 )fat
- regulate deposition of fat
- thermogenesis (brown fat)

Question 14

physiological control of T3 and T4

Answer 14

1) hypothalamopituitary axis
2) TSH
- anterior pituitary releases it
3) TRH

Question 15

metabolic actions of thyroid hormones

Answer 15

1) increases basically everything
- O2 consumption
- basal metabolic rate
- Na+/K+ ATPase
- erythropoiesis
- GI motility
- glucose metabolism
- lipolysis
- bone turnover

Question 16

hypothyroidism myzedema

Answer 16

1) insufficient iodine
2) hashimotos
3) thyroid surgery or radiation
4) insufficient thyroxine dose
5) genetic variations of TPO

Question 17

hyperthroidism thyrotoxicosis

Answer 17

1) thyroid cancer
2) grave’s
3) thyroxine overdose
4) genetic variations of TSHR

Question 18

hypothyroidism epidemiology

Answer 18

1) 3.7% in USA
2) in developing countries, up to 30% due to iodine deficiency
3) more in women and elderly

Question 19

hypothyroidism diagnosis

Answer 19

1) lethargy
2) swelling of face
3) brain fog, memory loss
4) wasting of tongue
5) hoarseness
6) slow speech, slow HR pulse

Question 20

hashimotos

Answer 20

1) problem with TPO
2) normally released from the gland, but it is recognized as foreign
- T cytotoxic cells destroy the follicle

Question 20

myxedema

Answer 20

1) glycosaminoglycans in the dermis
2) swelling

Question 21

thyroid replacement

Answer 21

1) synthetic hormones are preferred over animal preparations
2) T4 preparations are preferred bc of longer half life and control
- less active

Question 22

thyroid medications

Answer 22

1) l-thyroxine contains T2
2 ) desiccated thyroid
- animal
3) recombinant human TSH

Question 23

hyperthyroidism etiology

Answer 23

1) can be primary or secondary
2) autoimmune is graves disease

Question 24

hyperthyroidism epidemiology

Answer 24

1) 1/2000 in USA

Question 25

hyperthyroidism diagnosis

Answer 25

1) sweating
2) insomnia
3) HR goes up
4 )hair loss
6) nausea
7) goiter
8) trembling

Question 26

graves disease

Answer 26

1) TSH receptor is released from the gland
- recognized as foreign
2) plasma cells make autoantibodies
3)

Question 27

treamtn o fhyperthyroidism

Answer 27

1) removal of thyroid (ablation)
2) anti thyroid drug therapy
3) radiation

Question 28

thioureylenes

Answer 28

1) methimazole and propylthiouracil
- inhibit TPO
- PTU only inhibits T4 > T3 in tissue
2) onset of action is slow and need to deplete stocks

Question 29

potassium iodid

Answer 29

1) inhibit thyroidal peroxidase and thyroglobulin proteolysis
2) decreases size and vascularity of the hyperplastic gland
2) cautions
- can further hyperthyroidism in some patients

Question 30

radioactive iodine

Answer 30

1) 131 Iodine is concentrated by gland and emits beta rays to destroy cells

Question 31

iodinated contrast media

Answer 31

1) inhibit T4>T3

Question 32

propanolol

Answer 32

1) symptomatic relief of hyperthyroidism

Question 33

dental considerations

Answer 33

1) if well-controlled, you can receive any dental treatment