Pharm Tb4 Thyroid Drugs

Front 1

what is the M.O. of TH?

Back 1

T3 binds to the TH receptor increasing ATP turnover due to upregulation of Na/K ATPase

Front 2

what is the effect of TH on growth and metabolism?

Back 2

increased basal metabolic rate via increases in oxygen consumption in the heart, skeletal muscle, liver and kidney

Front 3

What are the effects of TH on the CV system?

Back 3

increased CO and HR and increases sensitivity to catecholamines (especially in the elderly, those with CV disease and those with long standing hypothyroidism)

Front 4

What is the effect of TH on musculature?

Back 4

fine hand tremor

Front 5

What is the effect of TH on sleep?

Back 5

increased TH cause fatigued wakefulness

Front 6

What is the effect of TH on lipids?

Back 6

increased lipid mobilizaiton and degradation

Front 7

What is Thyroid U.S.P?

Back 7

dessicated thyroid preparations used to treat hypothyroidism

Front 8

What are the pros and cons of dessicated thyroid preparations?

Back 8

cheap but has variation in acitivty and T3/T4 content

Front 9

Where from are dessicated thyroid preparations obtained?

Back 9

bovine sources

Front 10

what is liotrix?

Back 10

a fixed ratio thyroid preparation used to treat hypothyroidism

Front 11

what are the pros and cons of liotrix?

Back 11

standardized preparation with a fixed ratio of T3/T4 BUT T3 is not needed and causes significant adverse effects

Front 12

What are the adverse effects of T3?

Back 12

tremor, headache, palpitations, diarrhea

Front 13

What is Levothyroxine T4?

Back 13

the preferred preparation to treat hypothyroidism

Front 14

Why is levothyroxine the preferred treatment for hypothyroidism?

Back 14

it has fairly predictable results and lacks T3 = lacks adverse effects

Front 15

What is the problem with levothryoxine?

Back 15

there are problems with stability

Front 16

when should the levothryoxine dose be reduced?

Back 16

in older patients, those with cardiac diseae or long standing hypothyroidism

Front 17

how long dose it take to see the effects of thyroid agnets in treating hypothyroidism?

Back 17

>2 weeks, full resolution can take 3-6 months

Front 18

What happens to TSH when thryoid agents for the treatment of hypothyroidism are given?

Back 18

negative feedback on TSH- usually temporary but can be significant

Front 19

what is the affect of propranol to TH?

Back 19

it decreases conversion of T4 to T3 by inhibiting 5'deiodinase = decreases T3 and increases rT3 in the serum

Front 20

what is used to treat thyroid storm?

Back 20

propranolol

Front 21

what is used to treat thryotoxicosis?

Back 21

propranolol

Front 22

What are the interactions with hyperthyroidism and diabetes?

Back 22

hyperthyroidism increases the severity of diabetes = increase the dose of anti-diabetes drugs

Front 23

what is the interaction of estrogen and TH?

Back 23

estrogen increases TBG = decreases free T4, as seen in pregnancy

Front 24

what is the interaction of antacids, bile acid renins, calcium, iron and ciproflaxi with thyroid drugs?

Back 24

they decrease the absorption of thyroid drugs

Front 25

what is the interaction of phenobarbital and TH?

Back 25

phenobarbital increases the metabolism of TH

Front 26

What is the interaction of phenytoin and TH?

Back 26

phenytoin displaces TH from TBG and increases TH metaboism = mointor TSH levels

Front 27

What is the interactino of warfarin and TH?

Back 27

T4 increases the anticoagulant action

Front 28

what is methimazole?

Back 28

a thioamides, an anti-thyroid drug

Front 29

What is propylthiouracil?

Back 29

a thioamides, an anti-thyroid drug

Front 30

what is the M.O. of thioamides?

Back 30

thioamides inhibit oxidation and coupling steps of TH biosynthesis; high dose inhibits the conversion of T4 to T3

Front 31

What is the rate of onset of thioamides?

Back 31

SLOW - due to inhbition at the synthesis level

Front 32

When are thioamides used?

Back 32

to treat hyperthyroidism alone or with radioactive iodine; or as an adjunct prior to surgery; it is good for young persons with small glands and mild disease

Front 33

what are the adverse effects with thioamides?

Back 33

there is a low incidence of agrnulocytosis, especially with methimazole

Front 34

what is the absorption rate of methimazole?

Back 34

methimazole is completely absorbed at vairable rates, accumulated in the thyroid gland and secreted slower than PTU = MORE POTENT THAN PTU

Front 35

what is the absorption rate of PTU?

Back 35

rapidly absorbed, reaches peak levels after 1 hour

Front 36

Which thioamide is preferred in pregnany?

Back 36

PTU - because it is more strongly protein bound = crosses the placenta less readily

Front 37

Which thioamide is preferred in treatment of hyperthyroidism?

Back 37

methimazole because it can be given once per day - exception: pregnancy

Front 38

What is the M.O. of radioactive iodine?

Back 38

it is take up by the thyroid and destroys T4 producing cells = decreases TH production

Front 39

What are the pros and cons of radioactive iodine use?

Back 39

pros: high cure rate, easily administered, low expense, absence of pain, avoids risk of surgery; cons: chance of delayed hypothyroidism, multiple doses may be required and take months to years for effect, response is hard to evaulate

Front 40

When is radioactive iodine is contraindicated?

Back 40

in pregnancy and during nursing

Front 41

how do TH increase the sensitivity of catecholamines?

Back 41

by increasing the number of beta receptors

Front 42

What is the M.O. of iodides?

Back 42

inhibit organification and hormone release, decreases the size and vascularity of the thyroid gland

Front 43

what is the onset of iodides?

Back 43

rapid onset because they inhibit hormone release = 2-7 dyas for onset

Front 44

when are iodides used?

Back 44

in thyroid storm and in preoperative prep for surgery

Front 45

When should iodides NOT be used?

Back 45

if treatment with radioactive iodine seems likely

Front 46

what are the disadvantages of idodide use?

Back 46

increased intragladnular stores of iodine- should be given after onset of thiomide therapy, should NOT be used alone, avoid chronic use in pregnancy

Front 47

What are the adverse effects of iodides?

Back 47

acneiform rash, swollen salivary glands, mucous membrane ulceration, conjunctivitis, rhinorrhea, drug fever, metallic taste, bleeding disorders

Front 48

what is ipodate?

Back 48

oral iodinated contrast media

Front 49

what is iopanoic acid?

Back 49

oral iodinated contrast media

Front 50

what is diatrizoate sodium?

Back 50

IV iodinated contrast media

Front 51

What is the M.O. of iodinated contrast media?

Back 51

rapidly inhibit the conversion of T4 to T3 in the liver, kdiney, pituitary gland and brain

Front 52

when are iodionated contrast media used?

Back 52

in the treatment of thyroid storm, as alternatives when iodides or thiomides are contraindicated

Front 53

what is thyrotopin?

Back 53

thyroid drug is used in conjuction with a diagnostic dose of RAI in whole body thyroid metastatic surveys in patients who have undergone complete thyroidectomy secondary to thyroid carcinoma

Front 54

what is rTSH?

Back 54

pro-thyroid agent that is used as an anti-thyroid in treatment due to radioactive component

Front 55

what should be done in the treatment of myxedema and CAD?

Back 55

avoid provoking arrhythmia, angina or acute MI

Front 56

what should be done in the treatment of myxedema coma?

Back 56

use IV levothyroxine

Front 57

what is used to treat Grave's disease?

Back 57

anti-thyroid treatment - methimazole or PTU until spontaneous remission; thyroidectomy can be done or radioactive iodine - in patients over 21

Front 58

What is the product of deiodination of T4 in the outer ring?

Back 58

active T3

Front 59

What is the product of deiodination of T4 in the inner ring?

Back 59

reverse T3 = inactive