Endocrine (year 2)

Question 1

what pharmacological agents are used to treat hyperthyroidism?

Answer 1

radioiodine and thioureylenes

Question 2

what is the mechanism of action of radioiodine?

Answer 2

rapid selective uptake by thyroid and damaged cells, then emits short-range beta radiation that only effects thyroid follicle cell

Question 3

how long after radioiodine will T3 and T4 levels begin to normalise?

Answer 3

1-2 weeks

Question 4

how is radioiodine administered?

Answer 4

injection

Question 5

what special precaution must be taken when giving a dog radioiodine?

Answer 5

hospitalised in isolation facilities for at least 2 weeks and excreta handled carefully

Question 6

what species is radioiodine mainly used in?

Answer 6

cats

Question 7

what is an adverse effect of radioiodine?

Answer 7

may cause hypothyroidism

Question 8

name the thioureylenes

Answer 8

carbimazole and thiamazole

Question 9

what is the mechanism of action of thioureylenes?

Answer 9

carbimazole is metabolised to methimazole which inhibits synthesis of thyroid hormones

Question 10

how are thioureylenes administered?

Answer 10

orally once a day

Question 11

what are the adverse effects of thioureylenes?

Answer 11

they are rare but may cause kidney problems in older cats

Question 12

what drugs are used for hypothyroidism?

Answer 12

levothyroxine and liothyronine

Question 13

what is the mechanism of action of levothyroxine and liothyronine?

Answer 13

they are identical to the endogenous version and given as replacement therapy

Question 14

how are levothyroxine and liothyronine administered?

Answer 14

orally

Question 15

what is the adverse effects of levothyroxine and liothyronine?

Answer 15

hyperthyroidism, tachycardia, excitability, nervousness

Question 16

what agents can be used to treat adrenal disease?

Answer 16

glucocorticoid receptor agonist
mineralocorticoid receptor agonist
adrenal steroid synthesis inhibitors
dopamine receptor agonist

Question 17

what is the mechanism of action of glucocorticoid receptor agonist?

Answer 17

enter cells by simple diffuse and synthetic glucocorticoids often aren’t protein bound

Question 18

how are glucocorticoid receptor agonists administered?

Answer 18

topically, orally, systemically

Question 19

what are the main uses of glucocorticoid receptor agonists?

Answer 19

replacement therapy for Addisons disease
anti-inflammatory
immunosuppressant

Question 20

describe some adverse effects of glucocorticoid receptor agonists

Answer 20

Suppression infection/injury response
Wound healing is impaired 
Cushing’s syndrome
Osteoporosis
Hyperglycaemia
Muscle wasting
Fluids/electrolyte imbalances 
Oedema
Reduced milk yield s
GI ulceration
Abortion in late pregnancy
Laminitis

Question 21

how are mineralocorticoid receptor agonists administered?

Answer 21

inject

Question 22

what are mineralocorticoid receptor agonists used for?

Answer 22

replacement therapy for dogs with Addisons disease

Question 23

what are the adverse effects of mineralocorticoid receptor agonist?

Answer 23

they are rare but may cause polyuria or hypokalaemia

Question 24

name a mineralocorticoid receptor antagonist

Answer 24

spironolactone - covered in diuretics

Question 25

what is the mechanism of action of adrenal steroid synthesis inhibitors?

Answer 25

inhibits production of glucocorticoids, mineralocorticoid and sex hormones by inhibiting 3beta-hydroxysteroid-dehydrogenase

Question 26

name an adrenal steroid synthesis inhibitors

Answer 26

Trilostane

Question 27

how are adrenal steroid synthesis inhibitors administered?

Answer 27

orally

Question 28

what are adrenal steroid synthesis inhibitors used for?

Answer 28

treat hyperadrenocorticism by suppressing glucocorticoid production

Question 29

what are dopamine receptor agonists used for?

Answer 29

treat equine cushing

Question 30

what is the route of administration of dopamine receptor agonists?

Answer 30

oral

Question 31

name a dopamine receptor agonists

Answer 31

pergolide

Question 32

what are two pharmacological agents used to effect calcium metabolism?

Answer 32

calcium salts and vitamin D preparations

Question 33

what are calcium salts used for?

Answer 33

replacement therapy for dietary deficiency, hypocalcaemia, hyperphosphataemia

Question 34

what calcium salt is used to treat hyperphosphataemia and how does it work?

Answer 34

calcium carbonate - an antacid that is poorly absorbed and binds to phosphate in the gut

Question 35

give some examples of calcium salts used to effect calcium metabolism

Answer 35

calcium gluconate, calcium carbonate, calcium chloride, calcium borogluconate

Question 36

how are calcium salts administered?

Answer 36

orally or parenterally (calcium gluconate)

Question 37

what are some adverse affects of calcium salts?

Answer 37

cause GI upset, cardiac arrythmias

Question 38

how are vitamin D preparations administered?

Answer 38

orally

Question 39

what are vitamin D preparations used to treat?

Answer 39

hypocalcaemia following thyroidectomy or immune mediated hypoparathyroidism

Question 40

what are the adverse effects of vitamin D preparations?

Answer 40

hypercalcaemia, hyperphosphataemia, nephrocalcinosis

Question 41

what two drugs can be used yo treat diabetes mellitus?

Answer 41

insulin and oral hypoglycaemics

Question 42

what are feline and canine insulin replacements made from?

Answer 42

canine - porcine | feline - bovine

Question 43

what is the mechanism of action of insulin receptor agonists?

Answer 43

bind to insulin and have the same response as endogenous insulin

Question 44

how are insulin replacements administered?

Answer 44

injected usually subcutaneously | oral preparations will be broken down by GI tract as they are peptides

Question 45

what is insulin replacements used for?

Answer 45

treat type 1 diabetes hyperglycaemic emergencies emergency hyperkalaemia

Question 46

what are the adverse effects of insulin receptor agonists?

Answer 46

hypoglycaemia insulin resistance - antibodies or stress induced insulin receptor desensitisation

Question 47

name an oral hypoglycaemic drug

Answer 47

sulphonureas - glipizide

Question 48

what is the mechanism of action of sulphonureas?

Answer 48

they stimulate insulin secretion from beta cells and increases insulin sensitivity - requires some normal beta cell function

Question 49

what are sulphonureas used to treat?

Answer 49

type 2 diabetes in cats

Question 50

what might be an adverse effect of the use of sulphonureas?

Answer 50

hypoglycaemia