Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology -- Test #5 > Pharmacology of Thyroid Hormone > Flashcards

Pharmacology of Thyroid Hormone Flashcards

1
Q

Iodide uptake from circulation occurs via

A

Sodium-Iodide symporter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Iodide is extruded from the thyroid follicle by…

A

Pendrin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Oxidation of iodide is catalyzed by…

A

Thyroid Peroxidase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Coupling of mono and di-iodotyrosyl residues is catalyzed by…

A

Thyroid Peroxidase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

T4–>T3 peripheral conversion is mediated by…

A

Types I II and III 5’ deiodinases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Some drugs that decrease binding of thyroxine to TBG

A 
Glucocorticoids
Androgens
Salicylates
Anti-seizure meds (phenytoin, carbamazeine)
Furosemide
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Effect of severe myxedema on thyroid absorption

A

Severely hampered

Administer via IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Important of Thyroid binding proteins. When are they high? Low?

A

They have a major effect on the rate of the degradation of thyroid hormone.
High – Pregnancy
Low – Nephrosis, Cirrhosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Thyroid hormone is excreted as

A

bile –> stool

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Important thyroid preparations

A 
Levothyroxine Sodium (synthetic T4)
Liothyronine Sodium (T3)
Liotrix (Mix of the above two, 4:1 respectively)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Effects of soy/bran/coffee on thyroid hormone absorption

A

Attenuate it, take 30-60 minutes before meals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Why would you use Liothyronine Sodium instead of levothyroxine

A

Recent hypothyroidism, overtreatment with anti-thyroid drugs

After radioiodide treatment, post htyroidectomy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Details of treatmnet of simple goiter

A

Replacement therapy to drop TSH levels and decrease size of the goiter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

In thyroid patients contraindicated for betablockers (asthma) treat with….to control tachycardia

A

Diltiazem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

______ disease may be associated with nodular thyroid tumors

A

Plummer’s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Six categories of major anti-thyroid drugs

A
  1. Blockers of Thyroid Hormone synthesis
  2. Ionic inhibitors that block iodide transport
  3. Iodide (blocks thyroid hor. synthesis at high conc)
  4. Iodinated Contrast (blocks T3-4 conversion and synth)
  5. Radioactive Iodine (destroys gland with ionizing radiation
  6. Lithium (suppresses synthesis and release)
17
Q

Drugs that block thyroid hormone synthesis

A

1, Thioamides (Methimazole, PTU, Carbimazole)

  1. Aniline Derivatives (Sulfathiazole)
  2. Polyhydric Phenols (Resorcinol)
18
Q

How do thioamides work?

A

Block Thyroid Peroxidase
(no oxidation, organification)
PTU also blocks peripheral T3–>T4

19
Q

Important details about thioamide absorptiona dn degradation

A

PTU bioabailability is 50-80%. survives first liver pass.
Methimazole is completely absorbed, but slowly.
Both accumulate in thyroid and are excreted mostly in glucuronidated conjugates in urine.

20
Q

Difference between Methimazole and PTU

A

Meth. is about 10x as potent

PTU is for people who can’t meth and preggers

21
Q

Important bad side effect from thioamide treatment

A

Agranulocytosis
PTU - Hep
Meth – Jaundice

22
Q

What is the Wolf-Chaikoff effect

A

Iodide inhibits the synthesis of iodotyrosine and iodothhyronine

23
Q

Most important clinical effect of iodide

A

Inhibits the release of thyroid hormone

24
Q

Common adverse effects of iodide

A

Rash, Swollen Salivary Glands, Metallic Taste, COnjunctivitis

25
Q

How do iodinated contrast materials (ipodate, diatrizoate, iohexol) treat hyperthyroid

A

They are potent inhibitors of the deiodination of T4–>T3

26
Q

Why use iodinated contrast material to control hyperthyroid

A

Effective, relatively non-toxic

Helps in thyroid storm if thioamines and iodides are contraindicated

27
Q

Radioiodine is used for…

A

Hyperthyroidism
131 – trtment of choice for older patient
not for pregnant, nursing
Used for diagnosis w/ RI Uptake tracking

28
Q

Psych drug that should cause you to periodically evaluate thyroid Fxn

A

Lithium

Pharmacology -- Test #5 (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions