thyroid/parathyroid 37

Question 1

actions of the thyroid gland

Answer 1

produces two thyroid hormones using iodine from diet

• tetraiodothyronine (levothyroxine, T4)
• triiodothyronine (liothyronine, T3)

removes iodine from blood, concentrates it, and prepares it for attachment to tyrosine

Question 2

functions of thyroid hormones

Answer 2

metabolism
thermoregulation
O2 demands, cardiac output, blood volume
enzyme system activity
growth/development

Question 3

hypothyroidism causes

Answer 3

absence of thyroid gland
deficient dietary iodine
lack of functioning thyroid tissue 2/2 tumor, autoimmune disorders
lack of TRH r/t tumor, hypothalamus disorder

Question 4

hypothyroidism treatment

Answer 4

levothyroxine (synthroid, levoxyl, levo-T, levothroid) is a synthetic salt of T4

Question 5

levothyroxine action

Answer 5

increases metabolic rate of body tissues, increasing O2 consumption, respiration, HR

acts as replacement for natural thyroid hormone and used as replacement therapy in hypothyroidism

Question 6

levothyroxine pharmacokinetics

Answer 6

given PO
metabolized in liver
excreted in bile
onset 6-8 hrs

Question 7

levothyroxine contraindications

Answer 7

hypersensitivity
thyrotoxicosis
acute MI complicated by hypothyroidism

Question 8

levothyroxine adverse effects

Answer 8

HTN, tachycardia, sweating, heat intolerance
arrhythmias
anxiety
headache
GI irritation (n/v/d)

Question 9

levothyroxine interactions

Answer 9

“many” – powerpoint

Question 10

levothyroxine interventions

Answer 10

max therapeutic effect: replacement therapy is lifelong; monitor cardiovascular response and serum thyroid function

min adverse effect: young adults without CAD can begin full replacement dose of levothyroxine

Question 11

levothyroxine + pregnancy

Answer 11

pregnancy category A

Question 12

hyperthyroidism causes

Answer 12

Graves’ disease

excessive amounts of thyroid hormones are produced and released into circulation

Question 13

hyperthyroidism s/s

Answer 13

increased body temp, heat intolerance, flushing
tachycardia, palpitations, HTN
thin skin
weight loss, amenorrhea
goiter

Question 14

hyperthyroidism treatment

Answer 14

thyroid-hormone antagonist drugs
surgery
radioactive iodine

prototype: methimazole (MMI)

Question 15

methimazole action

Answer 15

palliative treatment of hyperthyroidism that inhibits synthesis of thyroid hormones

Question 16

methimazole pharmacokinetics

Answer 16

given PO
metabolized in liver
excreted in urine

Question 17

methimazole contraindications

Answer 17

hypersensitivity

Question 18

methimazole adverse effects

Answer 18

hives, itching, rash
joint swelling, arthralgia
vertigo
drowsiness
n/v
altered taste sensation

Question 19

methimazole drug interactions

Answer 19

beta-blockers
theophylline
warfarin

Question 20

methimazole interventions

Answer 20

max therapeutic effect: ensure proper administration

min adverse effect: blood tests to monitor hematologic and thyroid function; monitor bone marrow function

Question 21

iodine solution (Iugol’s) actions

Answer 21

cause thyroid cells to become oversaturated with iodine and stop producing thyroid hormone

Question 22

iodine solution indications

Answer 22

presurgical supposition of thyroid gland
acute thyrotoxicosis
emergency thyroid blocking in radiation emergency

Question 23

iodine solution pharmacokinetics

Answer 23

given PO
metabolized in liver
excreted in urine

Question 24

iodine solution adverse effects

Answer 24

hypothyroidism, goiter
swelling of salivary glands
iodism (metallic taste, sore mouth/throat/gums, n/v/d, cold sx)
allergic rxn

Question 25

iodine 131 (radioactive therapy)

Answer 25

treatment for thyroid cancer
alternative to surgery
pregnancy category X !!!!!!

Question 26

propylthiouracil (PTU)

Answer 26

inhibits conversion of T4 to T3
usually used prior to surgery
treats thyrotoxic crisis

Question 27

hypoparathyroidism

Answer 27

absence of parathormone

most likely to occur with accidental removal of parathyroid glands during thyroid surgery

Question 28

hyperparathyroidism

Answer 28

excessive production of parathormone

2/2 parathyroid tumor or genetic disorder

Question 29

Paget’s disease

Answer 29

genetic disorder

overactive osteoclasts eventually replaced by enlarged, softened bony structures

Question 30

Paget’s disease s/s

Answer 30

deep bone pain
headaches
hearing loss

Question 31

antihypercalcemic drugs

Answer 31

treat Paget’s disease
inhibit bone resorption of calcium

prototype calcitonin

Question 32

antihypocalcemic drugs

Answer 32

manage hypocalcemia in patients undergoing chronic renal dialysis

treatment of hypoparathyroidism