Term
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Definition
Tx: Drug of choice for thyroid hormone replacement,
Thyroid cancer: suppresses pituitary TSH,
Myxedema coma (urgent!)
Ax: Synthetic hormone, peripheral activation to T3, acts on mitochondria and alters gene expression
SE: rare if proper dosing, excess dosing causes hyperthyroidism, can exacerbate acute MI
Ms: oral F=80%, ~35% converted to T3, t½=7days,
takes a few weeks to work
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Term
Propylthiouracil
Methimazole |
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Definition
Tx: hyperthyroidism, do not use methimazole in pregnancy (crosses placenta, enter breastmilk),
Ax: Thioamines - compete w/ thyroglobulin for iodine→↓T3/T4 synth., propyl: inhibits thyroid peroxidase + T4/T3 conversion, methim: inhibits thyroid peroxidase only, potent
SE: goitrogens:↓T3/T4→↑TSH → gland hypertrophy,
agranulocytosis, arthralgias, rash (lupus-like), bradycardia, propyl: depletes prothrombin, methim: BM suppression |
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Term
Radioactive Iodine
(I-137)
Stable Iodide
(I-127) |
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Definition
Tx: 131: hyperthyroidism (Graves, hot nodulethyroid, etc.)
127: short-term block in radiation emergencies, ↓vascularity before surgery
Ax: 131: selective permanent thyroid destruction,
127: High levels inhibit T3/T4 synth. + release (Wolff-Chaikoff effect)
SE: Hypothyroidsim (overshoot), NOT for pulm edema or TB pts, 131: may worsen proptosis, serious fetal problems, 127: may worsen toxic goiter
Ms: enter thyroid follicular cells via Na+/I- symporter |
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Term
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Definition
Tx: Paget's, osteoporosis, alendro: male osteoporosis, etidro: hypercalcemia of malignancy/osteolytic cancer, NOT for hypocalcemia tx or preg.
Ax: Bisphosphonates inhibits mevalonate pathway in osteoclasts, blocks bone resorption→lower serum Ca2+ levels
SE: alendro: esophageal erosion if can't stay upright ½ hr, etidro: ↑fracture risk
Ms: ↓absorption w/ food (milk) |
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Term
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Definition
Tx: ↓serum Ca2+ in Paget's, ↑kidney excretion of Ca2+, Na+, PO4--, NOT for lactating women
Ax: secreted by thyroid parafollicular cells, binds + inhibits osteoclasts
SE: Flushing, rash, N/V, injection site inflamm.
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Term
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Definition
Tx: Vitamin D-dependent rickets, hypoparathyroidism
Ax: Provides Ca2+
Ms: IV for severe cases, less irritation than others
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Term
Calcitriol
(1,25 (OH)2 Vit D3) |
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Definition
Tx: Hypoparathyroidism, may ↑ bone formation, chronic renal dialysis pts,
Ax: ↑Ca absorption in GI, ↑bone mineralization, ↑renal Ca/PO4 reabsorp, inhibits PTH synth/release
SE: NOT for hypercalcemia pts, hx kidney stones, or preg, Metal taste, N/V |
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