Endocrine

Question 1

cushings disease =

Answer 1

hyperadrenocorticism

Question 2

addison’s disease =

Answer 2

hypoadrenocorticism

Question 3

what causes hyperadrenocorticism?

Answer 3

excess glucocorticoid production by the adrenals

Question 4

what do you call a functional mass of the adrenal medulla?

Answer 4

pheocromocytoma (remember phenooxybenzamine is the drug of choice!)

Question 5

what does a functional pituitary mass or pituitary dependent hyperadrenocorticism (PDH) produce?

Answer 5

ACTH

Question 6

what are the three targets for drug therapy of hyperadrenocorticism?

Answer 6

• adrenal gland tissue (i.e. surgical adrenalectomy)
• production of glucocorticoids
• production of ACTH

Question 7

how does mitotane target adrenal gland tissue?

Answer 7

cytotoxic to cells of the fasciculata

Question 8

T/F: mitotane has a narrow therapeutic index

Answer 8

TRUE

Question 9

what are the two types of doses you give with mitotane?

Answer 9

• high dose (induction)

- lower dose (maintenance)

Question 10

what might you worry about with sending client home with mitotane?

Answer 10

potentially immunogenic, can be dangerous for client! (esp. pregnant women), USE GLOVES!!

Question 11

how do you monitor adrenal function?

Answer 11

ACTH stimulation test

Question 12

what is an adverse effect of using mitotane?

Answer 12

oversuppression of adrenal function (can lead to adrenal collapse where lose glucocorticoids AND mineralcorticoids)

Question 13

what drugs used for hyperadrenocorticism should be monitored?

Answer 13

mitotane and trilostane

Question 14

how does trilostane target the production of glucocorticoids in the adrenal?

Answer 14

inhibits the enzyme (3B-hydroxysteroid dehydrogenase) in the cortisol production pathway blocking the cells ability to produce the end product

Question 15

what drug is most commonly used to treat cushings?

Answer 15

triolostane

Question 16

T/F: trilostane has a wider TI making it safer to use than mitotane

Answer 16

FALSE, triolostane also has a narrow TI but is easier to use safely than mitotane

Question 17

T/F: mitotane is started with a low dose and then increased to a high dose where trilostane is started with a high dose and then decreased to a low dose

Answer 17

FALSE, opposite

Question 18

T/F: ketoconazole’s clinical efficacy has been questioned

Answer 18

TRUE

Question 19

what are possible adverse effects of ketoconazole?

Answer 19

• potential for hepatotoxicity

- POTENT hepatic microsomal enzyme inhibitor

Question 20

how does pergolide target the production of ACTH by the pituitary?

Answer 20

=dopamine agonist, suppresses production of ACTH thus reducing cortisol production

Question 21

what drug is used to treat pituitary pars intermedia dysfunction in horses?

Answer 21

pergolide

Question 22

pituitary pars intermedia dysfunction is equivalent to what disease in canines?

Answer 22

cushings

Question 23

what is selegiline labeled to treat in dogs?

Answer 23

cognitive dysfunction

Question 24

what is the MOA of selegiline?

Answer 24

inhibits MAO-B which results in increased dopamine

Question 25

why does dr. boots think selegiline is useless?

Answer 25

methamphetamine is a byproduct, when given to an old dog with cushings it perks up and helps alleviate symptoms but the actual output of # of hormones don't actually improve

Question 26

deficient production of what causes hypoadrenocorticism (addison's)?

Answer 26

glucocorticoids +/- mineralcorticoids

Question 27

what is the primary cause of hypoadrenocorticism?

Answer 27

chronic destruction of the adrenal gland (typical and atypical)

Question 28

T/F: dopamine stimulates the anterior pituitary gland, therefore stimulating the adrenal gland to produce glucocorticoids

Answer 28

FALSE, dopamine is an inhibitor (gives negative feedback)

Question 29

what corticosteroids would be insufficient in iatrogenic adrenal insufficiency?

Answer 29

glucocorticoids, treat with prednisone

Question 30

T/F: iatrogenic adrenal insufficiency occurs when exogenous glucocorticoids are used chronically then stopped abruptly or adrenal glands are damaged through excessive action of drugs used to treat hyperadrenocorticism

Answer 30

TRUE, patient suffers insufficient adrenal output (chronic negative feedback) or adrenal glands were over suppressed

Question 31

between mitotane or trilostane which drug would result more rapid improvement if you needed to withdrawal the drug because of over suppressing the adrenal glands (over treating)?

Answer 31

trilostane, inhibits the enzyme whereas mitotane works on the cells of the fasciculata which means the body would need more time to regenerate the cells

Question 32

how does ketoconazole target the production of glucocorticoids in the adrenal?

Answer 32

inhibits enzymes in the steroid synthesis pathway

Question 33

is ketoconazole a hepatic microsomal enzyme inducer or inhibitor, and what effect might it have on other drugs?

Answer 33

INHIBITOR, might INCREASE half-life of other drugs bioinactivated through the P450 system