| Term 
 
        | Levothyroxine and liothyronine: MOA? Max effect seen after how long? Tox? |  | Definition 
 
        | activation of nuclear receptors, gene expression with RNA formation and protein synthesis.  6-8 wks. Symptoms of thyroid excess. |  | 
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        | Term 
 
        | What is propylthiouracil? What is the MOA? Duration of action? Onset? Tox? |  | Definition 
 
        | a thioamide, inhibits thyroid peroxidase reactions, blocks, iodine organification, inhibits peripheral conversion of T4 and T3.  DOA 6-8 hrs, delayed onset.  Nausea, GI distress, rash, agranulocytosis, hepatitis, hypothyroidism. |  | 
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        | Term 
 
        | What are lugol solution and potassium iodide? MOA? Indications? |  | Definition 
 
        | iodides, inhibit organification and hormone release, reduce size and vascularity of the gland.  Preparation for thyroidectomy |  | 
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        | Term 
 
        | What does propanolol do? Indications? Toxicity? |  | Definition 
 
        | Inhibits beta receptors, inhibits T4-T3 conversion in large doses.  Hyperthyroidism esp  thyroid storm, adjunct to control tachycardia, hypertension and A-fib.  Asthma, AV blockade, hypotension, bradycardia |  | 
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        | Term 
 
        | How does radioactive iodine (131) work? Indications? Who should avoid it? Max effect in how long? Tox? |  | Definition 
 
        | destroys thyroid parenchyma.  Hyperthyroidism, pts should be euthyroid or on B-blockers first, avoid in pregnancy or in nursing moms. 3-6 mo.  Sore throat, sialitis, hypothyroidism |  | 
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