Thyroid/Osteoporosis

Question 1

what 2 medications specifically can induce hypothyroidism

Answer 1

amiodarone (Cordarone)

lithium (Eskalith)

Question 2

how is primary hypothyroidism confirmed

Answer 2

elevated TSH and low free T4

Question 3

how is secondary hypothyroidism due to pituitary dysfunction confirmed

Answer 3

loe free T4

low TSH levels

Question 4

normal TSH

Answer 4

0.5-0.4

Question 5

Thyroid hormone interactions

Answer 5

drugs that can interfere with absorption such as questran, sucralfate (carafate), aluminum containing antacids, and calcium carbonate

Question 6

effect of increased estrogen on thyroid

Answer 6

increased estrogen production causes an increased in TBGs which, in turn, causes there to be more T4 in the bound inactive state rather than the free, active state. Will likely need higher dosages of thyroid hormone

Question 7

drugs that can decrease the affinity of T4 and T3 to TBGs causing a transient increase in free T4 and T3 levels

Answer 7

salicylates

high doses of furosemide

Question 8

thyroid hormone and coumadin

Answer 8

increases metabolism of vitamin k dependent clotting factors which raises the PT and risk of bleeding

Question 9

other drugs that alter metabolism of thyroid hormone

Answer 9

phenytoin

carbamazepine (tegretol)

Question 10

geriatric presentation of hypothyroid

Answer 10

may present with ataxia, paresthesias, and carpal tunnel syndrome
may also present with psychiatric manifestations such as depression and change in sensorium

Question 11

Causes of hyperthyroidism

Answer 11

graves disease (most common)
toxic nodular goiter
thyrotoxicosis factita (intentionally take high doses of thyroid hormone)

Question 12

3 ways to treat hyperthyroidism

Answer 12

antithyroid drugs
radioactive iodine ablation (tx of choice for >40)
surgery

Question 13

what happens to most patients with graves disease after treatment

Answer 13

they become hypothyroid

Question 14

antithyroid drugs

Answer 14

methimazole (Tapazole)

propylthiouracil (PTU)

Question 15

mech of action of antithyroid drugs

Answer 15

inhibits iodine organification

blocks conversion of T4 to T3 in the periphery

Question 16

what should providers tell patients to report when taking antithyroid drugs

Answer 16

sore throat and fever as this could signify a potentially fatal agranulocytosis
must obtain a CBC and dc drug if WBC low

Question 17

adjunctive agents used to manage hyperthyroidism

Answer 17

beta-blockers
iodine-containing compounds
lithium
glucocorticoids

Question 18

geriatric presentation of hyperthyroidism

Answer 18

weakness, dyspnea, anorexia, depression, or constipation

Question 19

drugs that can be affected when a hyperthyroid patient becomes euthyroid

Answer 19

increased effects of digoxin, metoprolol, and propranolol

Question 20

treatment of patients with thyroid nodules that are not cancerous

Answer 20

radioactive iodine and surgery

Question 21

subclinical thyroid disease

Answer 21

elevated TSH with a normal free T4 usually in a patient with no symptoms

Question 22

subclinical hyperthyroid disease

Answer 22

low TSH with normal T4 and T3

Question 23

Bone loss after age 30

Answer 23

occurs at about 10% each 10 years

Question 24

most common fractures in OP

Answer 24

vertebral compression fractures

fractures of distal radius and proximal femur

Question 25

makeup of long bones

Answer 25

thick outer layer of cortical (dense) bone and a thin inner layer of trabecular (spongy) bone

Question 26

makeup of short bones

Answer 26

mostly trabecular (spongy) bone with a thin layer of cortical (dense) bone

Question 27

what causes osteoporosis

Answer 27

an imbalance in bone remodeling that results in greater resorption than formation

Question 28

resorption-inhibiting drugs

Answer 28

estrogens bisphosphonates calcitonin selective estrogen receptor modulators (SERMs)

Question 29

recommended dosage of calcium for postmenopausal women

Answer 29

1200-1500mg/day

Question 30

recommended dosage of vitamin D3 (OP)

Answer 30

800-1000 iu

Question 31

mech of action of biphosphonates

Answer 31

inhibit bone resorption and increase bone density

Question 32

bisphosphonates drugs

Answer 32

alendronate (Fosamax) risedronate (Actonel) ibandronate (Boniva) zolendronic acid (Reclast)

Question 33

contraindications for bisphosphonates

Answer 33

history of esophageal problems, gastritis, or peptic ulcer disease

Question 34

side effects of bisphosphonates

Answer 34

``` esophagitis GI (diarrhea and abdominal pain) ```

Question 35

bisphosphonate interactions

Answer 35

absorption is decreased when taken with food, calcium, or iron

Question 36

mech of action of calcitonin

Answer 36

inhibits the action of osteoclasts not effective at preventing bone loss early in the postmenopausal period but it does increase bone mass in the spine leading to less vertebral compression fractures

Question 37

adverse events of calcitonin

Answer 37

nasal route can cause rhinitis (inspect nasal mucosa q6mo for ulceration)

Question 38

SERMs mech of action

Answer 38

mimics the effects of estrogen on bones without replicating the stimulating effects of estrogen on the breast and uterus

Question 39

SERMs effect on fractures

Answer 39

reduce risk of vertebral fractures but do not affect hip fractures

Question 40

bonus of SERMs

Answer 40

decrease total cholesterol and LDL cholesterol

Question 41

SERM drug

Answer 41

raloxifene (Evista)

Question 42

Hormone modifier used to treat OP

Answer 42

Teriparatide (Forteo)

Question 43

Mech of action of Forteo (hormone modifier)

Answer 43

stimulates new bone formation in trabecular and cortical bone by stimulating osteoblastic activity over osteoclastic activity

Question 44

administration of Forteo (teriparatide) hormone modifier

Answer 44

subQ at 20mcg

Question 45

contraindications to forteo (teriparatide) hormone modifier

Answer 45

``` pagets disease children previous bone radiation therapy history of skeletal malignancy metabolic bone disease hypercalcemia hyperparathyroidism hx of kidney stones ```

Question 46

adverse events of forteo (teriparatide) hormone modifier

Answer 46

may increase calcium levels and increase risk of dig toxicity

Question 47

RANK ligand inhibitor drug

Answer 47

denosumab (Prolia)

Question 48

mech of action of denosumab (Prolia RANK ligand inhibitor

Answer 48

targets and binds RANK ligand, inhibiting osteoclast formation, function, and survival, keeping osteoclasts from resorbing bone

Question 49

dosage of denosumab (Prolia RANK ligand inhibitor

Answer 49

60mg subQ q6mo

Question 50

contraindication to denosumab (Prolia RANK ligand inhibitor

Answer 50

pregnancy and hypocalcemia | caution with: creat clearance >30, immunocompromised, hx of small bowel excision

Question 51

adverse effects of denosumab (Prolia RANK ligand inhibitor)

Answer 51

musculoskeletal pain, infection, arthralgia, myalgia, abdominal pain

Question 52

what must OP patients have in addition to medication

Answer 52

calcium and vitamin D supplementation

Question 53

1st line therapy for OP

Answer 53

raloxifene or bisphosphonate therapy is used for prevention, bisphophonates are used for treatment

Question 54

2nd line therapy for OP

Answer 54

calcitonin, hormone modifier, or RANK ligand inhibitor recommended for those who fail to respond to or cannot tolerate 1st line therapy

Question 55

raloxifene (SERM) contraindications

Answer 55

pregnancy, hx of thromboembolic events

Question 56

how often should the DEXA scan be performed

Answer 56

every 2 years