Thyroid Disorders Flashcards
(17 cards)
1
Q
- The thyroid gland produces ___ which regulates what?
- what r the 2 thyroid hormones produced by the thyroid gland?
- The thyroid gland is the only one that can ___ which is required for production of both hormones
- Which thyroid hormone is more potent?
- Which one has a shorter half life?
- Thyroid hormone production is regulated by?
A
- thyroid hormones, regulates metabolism
- triiodothyronine (t3) and Thyroxine (T4)
- absorb iodine
- t3
- t3
- thyroid stimulating hormone (TSH)
2
Q
WHat is the unbound and ACTIVE form of thyroid hormone that’s monitored in pt’s with thyroid disorders?
A
Free T4 (FT4)
3
Q
- What is hypothyroidism?
- whats the most common cause of hypothyroidism?
- whats an uncommon but potentially fatal complication of hypothyroidism?
- its a life threatening emergency in which the initial treatment is?
A
- deficiency in T4, elevation in TSH
- hashimoto’s disease, an autoimmune condition in which a pt’s own antibodies attach the thyroid gland
- myxedema coma
- IV levothyroxine
4
Q
Diagnosis:
- Made using which two laboratory values? (state the name of lab value and the actual range itself)
- whats the main test to monitor thyroid function in those receiving thyroid hormone replacementw/drug treatment?
- how often should the TSH level and symptoms be monitored?
A
- LOW free T4: normal range 0.9-2.3 ng/dL
- HIGH TSH: normal range 0.3-3 mIU/L
- TSH
- every 4-6 weeks
4
Q
Too high of a thyroid hormone replacement dose in elderly pt’s can cause what?
A
atrial fib and fractures
5
Q
whats the DOC for treatment of hypothyroidism?
A
Levothyroxine (t4)
5
Q
Hypothyroidism TX:
- Levothyroxine
-what is it?
-Brand names?
-this is ____
-One should check the therapeutic equivalence of a generic to a brand in the ____ - Levothyroxine
-full replacement dose?
-if a patient has known CAD, what should the starting dose be? - Thyroid, Desiccated USP
-what is it?
-Brand name? - Liothyronine
-what is it?
-brand name?
A
- T4
-synthroid, levoxyl, unithroid
-doc
-orange book - 1.6 mcg/kg/day (IBW)
-12.5-25 mcg daily - T3 and T4
-armour thyroid - T3
-cytomel
6
Q
Hypothyroidism Drugs:
- General warnings?
- Monitoring for? and how often?
- Levothyroxine PO should be taken with ____ at the same time each day for consistent absorption
- when should the levothyroxine be taken?
- Know that levothyroxine tablet colors are ___ and do not change between manufacturers
- Levothyroxine IV to PO ratio?
- Why can Liothyronine cause fluctuations in T3 levels?
A
- decr dose in cardiovasc disease
- TSH levels and clinical sx’s every 4-6 weeks until levels r normal
- water
- at least 60 mins before breakfast or at bedtime (at least 3 hrs after the last meal)
- standard
- 0.75:1
- shorter half life
7
Q
DDI’s: Drugs that decr the effect of thyroid replacement hormone tx
- Drugs that DECR LEVOTHYROXINE ABS (5)
- what should you do with these drugs and levothyroxine administration?
A
- anatacids + polyvalent cations containing iron, Ca, Aluminum, or Magnesium
MVI
Cholestyramine
Sevelamer
Sucralfate
- separate doses by 4 hrs from thyroid replacement therapy
8
Q
Hyperthyroidism:
- overactive thyroid or ___
- what would the labs look like if you had hyperthyroidism?
- whats the most common cause of hyperthyroidism?
- what is grave’s disease?
- drug induced causes of hyperthyroidism include?
A
- thyrotoxicosis
- FT4 is HIGH, TSH is low
- grave’s disease
- autoimmune disorder where the antibodies stimulate the thyroid to produce too much t4
- iodine, amiodarone, and interferons
9
Q
Treatment of HYPERthyroidism:
- what treatment methods r available?
- with any treatment decision, pt can be treated with ___ first for symptom control to reduce what?
- how long does it take to control symptoms?
- once symptoms r controlled, how should the dose be changed?
A
- antithyroid medications.
-destroying part of the gland via radioactive idoine or surgery - beta blockers
-palpitations, tremors, tachycardia - 1-3 months of tx w/antithyroid meds at HIGH DOSES to control symptoms
- dose should be reduced to prevent hypothyroidism from occuring
10
Q
Hyperthyroidism Drugs: Thionamides
- MOA?
- what r the two drugs?
- Boxed warnings for PTU? (2)
- General warnings? (3)
- Side effects? (1)
- In general, what is the DOC in these situations?
- PTU is preferred in ____
- for pregnancy, which drug do you use in 1st trimester and which for 2nd/3rd?
A
- inhibit the synthesis of thyroid hormones by blocking the oxidation of iodine in the thyroid gland; PTU also inhibs peripheral conversion of T4 to T3
- Propylthiouracil (PTU) and Methimazole (tapazole)
- severe liver injury and acute liver failure
-pregnancy: PTU preferred in the 1st trimester - hepatotoxicity, agranulocytosis (bms), DILE
- GI upset
- methimazole (due to lower risk of liver damage)
- thyroid storm
- PTU preferred in 1st trimester; methimazole can be used in the 2nd and 3rd trimesters
11
Q
Hyperthyroidism Drugs: Iodides
- MOA?
** the book didnt have much else to say about this drug class
A
- temporarily inhibit secretion of thyroid hormones (effect will not be maintained)
12
Q
Potassium Iodide Use After Exposure to Radiation:
1. What does Potassium Iodide do?
A
- blocks the accumulation of radioactive iodine in the thyroid gland, thus preventing thyroid cancer
13
Q
What is thyroid storm?
*Signs and sx’s on flashcard written
A
life threatening medical emergency characterized by decompensated hyperthyroidism
14
Q
DRUG TX THYROID STORM:
- Antithyroid drug therapy : which is preferred?
- inorganic iodide therapy such as?
- beta blocker such as?
- Systemic steroid such as?
- Aggressive ____ with tylenol and cooling blankets + other supportive tx’s
A
- PTU
- SSKI or Lugol’s solution
- propranolol
- dexamethasone
- cooling
15
Q
Pregnancy and HYPOthyroidism:
- whats a safe and reccomended tx?
- pregnant women treated w/thyroid hormone replacement will require how much of a dose change?
A
- levothyroxine
- 30-50% incr in the dose
