Thyroid

Question 1

what is the drug of choice for hypothyroidism

Answer 1

levothyroxin

Question 2

what is the chemical structure of levothyroxin

Answer 2

L-isomer of t4

Question 3

what is the drug with the chemical structure of T3 and what is its indication

Answer 3

liothyronine, used for myxedema coma

Question 4

Which drug has the longer half-life, levothyroxin or liothyronine

Answer 4

levothyroxin (t4) gives it a prodrug buffer concentration in blood good for different metabolic situations

Question 5

why give liothyronine for myxedema coma

Answer 5

quick onset for life threatening situations

Question 6

when do you give radioactive iodide 131

Answer 6

hyperthyroidism and thyrotoxicosis

Question 7

what is the MOA of radioactive iodide 131

Answer 7

emits beta particles causing local destruction of the thyroid gland

Question 8

What is the concern regarding radioactive iodide 131

Answer 8

may cause hypothyroidism after too much destruction

Question 9

what role does the na/I symporter play in the uptake of radioactive iodide 131?

Answer 9

it cannot distinguish between the radioactive form and the endogenous form of 127.

Question 10

what is the wolf chaikoff effect

Answer 10

increase in iodide inhibits thyroid hormone synthesis and release because the NA/ I- symporter is down regulated

Question 11

what is the use of potassium iodide/inorganic iodide

Answer 11

given before thyroid gland surgery because iodide reduces valcularization and size of the gland making excision easier

Question 12

why can’t potassium iodide be given chronically to hyperthyroid patients

Answer 12

only causes a transient suppression of hormone release, after a while the hormones are back to normal

Question 13

what are the 2 thioamines

Answer 13

propylthiouracil and methimazole

Question 14

what is the MOA of thioamines

Answer 14

compete with thyroglobulin for oxidized iodide inhibiting organification and coupling INHIBITS THYROID PEROXIDASE

Question 15

When do you see the effects of thioamines

Answer 15

2 weeks later because of preformed hormone, affects synthesis not secretion

Question 16

what drugs cause goiter formation?

Answer 16

thioamines

Question 17

Why does thioamines cause goiter?

Answer 17

the increase in TSH due to the decrease in hormone causes thyroid hypertrophy.

Question 18

what thioamine is the drug of choice in clinical practice?

Answer 18

methimazole because it only requires 1 dose a day (longer half life ) and has a less adverse profile

Question 19

what are the 2 indications of propothiouracil?

Answer 19

thyroid storm, and first trimester of pregnancy

Question 20

why is propothiouracil used in thyroid storm

Answer 20

block thyroid peroxidase but also inhibits the conversion of t4 to t3 in peripheral cells

Question 21

what side effect can methomixazole cause in pregnancy?

Answer 21

aplasia cutis

Question 22

What is the regimen of thyroid drugs given for pregnancy?

Answer 22

propothiouracil for first trimester (upto 13 weeks) and then give methimazole for the rest.

Question 23

What class of drugs can be used to stop symptoms of hyperthyroidism?

Answer 23

beta blockers

Question 24

What two beta blockers are used?

Answer 24

propanolol (nonspecific) and esmolol

Question 25

What is the specific use of esmolol dealing with hyperthyroidism?

Answer 25

used in thyroid storm because of rapid onset and short elimination 1/2 life.

Question 26

what is amiodarone?

Answer 26

antiarrythmic drug

Question 27

how can amiodarone cause hypothyroidism

Answer 27

has a lot of iodide creating a wolf chaskoff like effect

Question 28

how can amiodarone cause hyperthyroidism

Answer 28

Type 1 thyrotoxicosis --> increased iodide leads to increased thyroid synthesis and release Type 2 Throiditis --> autoimmune thyroiditis is induced that leads to release of excess thyroid hormone from the colloid.

Question 29

how does amiodarone effect thyroid hormone in the peripherally?

Answer 29

inhibits type 1 deiodinase resulting in decrease conversion of T4 to T3 and increased rT3.

Question 30

When should you give IV insulin?

Answer 30

diabetic type 1 ketoacidosis

Question 31

what are the two alpha glucosidase inhibitors?

Answer 31

acarbose and miglitol

Question 32

what is the MOA of acarbose and miglitol

Answer 32

bind to alpha glucosidase enzmes and inhibit the cleavage of carbs to glucose and reside the postprandial peak in glucose.

Question 33

what are the 3 limitations of alpha glucosidase inhibitors?

Answer 33

only effective when taken with meals, cause diarrhea, flatulence , contraindicated with inflammatory bowel disease

Question 34

what are the 2 indications of acarbose and miglitol?

Answer 34

post prandial mild hyperglycemia, and new onset patients with mild hyperglycemia

Question 35

sulfonyl and meglitinide MOA

Answer 35

bind to the SUR 1 subunit inhibiting the K+/ATP channel causing depolarization and increased insulin release from the cell.

Question 36

what are the two first generation sulfonylureas

Answer 36

chlorpromide and tolbutamide

Question 37

What are the 3 second generation sulfonylureas

Answer 37

Glimepiride, gpizide, glyburide

Question 38

what are the 2 megliinides

Answer 38

Nateglinide and repaglinide

Question 39

what is the difference between sulfonylureas and meglitinides?

Answer 39

both bind to SUR 1 subunits causing depolarization and increasing insulin release, however they bind to different subunits.

Question 40

2 adverse effects of insulin secratogues are

Answer 40

hypoglycemia and weight gain

Question 41

when should you avoid sulfonryl ureas?

Answer 41

patient with a sulfa drug allergy

Question 42

what is the MOA of metformin?

Answer 42

biguanide that decreases glucose production in the liver by increasing AMPK.

Question 43

what else does metformin inhibit?

Answer 43

gluconeogenesis in the liver, cholesterol synthesis and fatty acid synthesis

Question 44

what are the benefits of metformin over insulin secratogues

Answer 44

lower lipid profiles and a decrease in weight

Question 45

what is the major adverse effect of metformin

Answer 45

lactic acidosis from shutting away metabolic acids through gluconeogenic pathways.

Question 46

what is the b-cell hormone that is co -secreted with insulin

Answer 46

amylin

Question 47

what is the name of an amylinin analogue

Answer 47

pramlintide

Question 48

what are the two GLP-1 analogues?

Answer 48

exenatide and liraglutide

Question 49

What is the main adverse effect of GLP-1 analogues?

Answer 49

acute pancreatitis

Question 50

what is the MOA of GLP-1 analogues?

Answer 50

increase secretion of insulin by pancreatic B-cells in a glucose dependent manner, suppresses glucagon, slows emptying, decreases appetite

Question 51

what is the MOA of DPP 4 inhibitors?

Answer 51

prolong GLP-1 by inhibiting DPP 4, promote insulin secretion and decrease glucagon.

Question 52

What is the respiratory infection caused by DPP 4 inhibitors?

Answer 52

respiratory infection

Question 53

what are the 3DPP inhibitors?

Answer 53

sitagliptin, saxagliptin, linagliptin

Question 54

what is the MOA of TMZs?

Answer 54

insulin sensitizers that enhance the function of insulin at target tissues and is a synthetic ligand which affects adipose cell differentiation and lipid metabolism

Question 55

where does TMZ cause fatty acids to go?

Answer 55

adipose tissue rather than skeletal, muscle or liver.

Question 56

what is one side effect of TMZ related to its MOA?

Answer 56

bone fractures and weight gain

Question 57

what is TMZ's current contraindication

Answer 57

hepatotoxiciy

Question 58

what are the 2 TMZs?

Answer 58

rosiglitazone and pioglitazone

Question 59

what does rosiglitazone cause?

Answer 59

myocardial infarction (only give to those who couldnt be saved otherwise.)

Question 60

what is the MOA of sglt2 inhibitors?

Answer 60

inhibit SGLT in renal tubules to reduce glucose reabsorption

Question 61

current indication of SGLT2 inhibitors?

Answer 61

adjunct to diet and exercise in type 2 diabetic patients

Question 62

what is the MOA of diazoxide?

Answer 62

bind to sur1 subunit of k+/ATP and stabilizes open state so B- cells remain hpyerpolarized and less insulin is released.

Question 63

When is diazoxide used?

Answer 63

stabilize hypoglycemia preoperatively and decrease BP in hypertensive state

Question 64

when should you administer gluccagon?

Answer 64

treat hypoglycemia