Nurs 8024 module 11 - 12
Primary hypothyroidism - correct answer ✔abnormality in the thyroid gland
itself (↑TSH, ↓FT4)
Secondary hypothyroidism - correct answer ✔hypothyroidism is due to lack
of pituitary TSH (↓TSH, ↓FT4)
Drugs that cause goiter - correct answer ✔Lithium, amiodarone,
propylthiouracil, methimazole, phenylbutazone, sulfonamides, interferon
Factors affecting levothyroxine aborption - correct answer ✔Should be taken
on an empty stomach, without other medications, supplements, or food for 1
hour, or 4 hours after the last meal
•fasting administration helps keep TSH target range
T4 Dosing Considerations - Elevated TSH - correct answer ✔typically
indicates underreplacement
•Before increasing dosage, assess for angina, diarrhea, malabsorption
•Maintenance dose should be continued w/ same brand
•slight differences in absorption
T4 requirements increase with - correct answer ✔oral estrogen therapy
•Increase T4 dose 30% as soon as pregnancy is confirmed
what to avoid with T4 administration? - correct answer ✔administration with
binding agents
,•iron, aluminum hydroxide antacids, calcium supplements, soy milk; or with
bile acid-binding resins (cholestyramine)
hyperthyroidism/thyrotoxicosis - correct answer ✔Hyperthyroidism is a
hypermetabolic state resulting from excess thyroid hormone
•Affects 2% of women and 0.2% of men in their lifetimes
Expected labs in thyrotoxicosis - correct answer ✔Suppressed TSH +
elevated thyroid hormone levels (↑Free T4, ↑Free T3)
Triad of Grave's Disease - correct answer ✔1. Hyperthyroidism
2. Ophthalmopathy
3. Dermopathy
Medication tx of hyperthyroidism - correct answer ✔*Thioamides*
(Methimazole, Propylthiouracil(PTU)
*Iodides*
symptomatic management of hyperthyroidism - correct answer ✔Beta-
Blockers
Thiomides MOA - correct answer ✔*First line RX*
inhibit thyroid peroxidase reactions, iodine organification, and peripheral
conversion of T 4to T
,Thiomides pharmacokinetics - correct answer ✔Oral, delayed onset (3-4wks)
Thioamides ADE - correct answer ✔Nausea, GI symptoms, rash,
hypothyroidism
•Serious side effects rare: agranulocytosis, hepatitis, vasculitis, aplastic
anemia (0.2 - 0.5%)
Iodides MOA - correct answer ✔Inhibits iodine organification & hormone
release
•reduces size & vascularity of thyroid gland
Iodides Pharmicokinetics - correct answer ✔Oral, rapid onset of activity
(within 2-7 days)
Iodide ADE - correct answer ✔Rare- avoid in pregnancy
advantages of thionamides - correct answer ✔Chance of permanent
remission
Some patients avoid permanent hypothyroidism
Lower initial cost
Disadvantages of THionamides - correct answer ✔Minor side effects: rash,
hives, arthralgias, transient granulocytopenia, gastrointestinal symptoms
, Major side effects: agranulocytosis, vasculitis (lupus-like syndrome), hepatitis
Risk of fetal goiter, hypothyroidism, and birth defects if pregnant
Requires more frequent monitoring
B-Blocker use for thyroid s/s - correct answer ✔Provide symptom relief-
helps to control adrenergic manifestations •Propranolol inhibits peripheral
conversion of T 4to T 3
•Propranolol- drug of choice
•Can use others... Atenolol, metoprolol
•Caution with CHF, asthma
Pregnancy considerations with hyperthyroidism - correct answer ✔Almost
solely caused by Graves' disease
•Preferred Rx - treatment with 131 I prior to pregnancy
•PTU during 1st trimester, (MMI assoc w/ fetal abn)
•Subtotal thyroidectomy in 2nd trimester is an option
Pregnancy considerations with hypothyroidism - correct answer ✔Adequate
levothyroxine essential for early fetal brain development