Hyperthyroidism
Adverse events of thioamides
CNS - fever, HA, paresthesias General - Rash, arthralgia, urticari GI - jaundice, hepatitis Hematologic - agranulocytosis, leukopenia, bleeding
List the different type of hyperthyroidism
1. Graves' disease (most common) 2. Toxic multinodular goiter (MNG), toxic adenoma, and exogenous thyroid hormone ingestion
Three primary ways of treating hyperthyroidism.
1. Surgery 2. Radioactive iodine (RAI) (tx of choice in most common forms!) 3. Antithyroid (thioamide) drugs
Patient instructions for iodides
1. dilute w/water or fruit juice to improve taste 2. Notify MD if fever, skin rash, metallic taste, throat swelling, or burning of the mouth occur
What comprises Lugol's solution?
5% iodine and 10% potassium iodide. Delivers 6.3 mg iodine per drop
Define thyroid storm
A life-threatening sudden exacerbation of hyperthyroidism. Sx: fever, tachycardia, delirium, and coma
Definition of hyperthyroidism
AKA thyrotoxicosis. Clinical syndrome where the tissues are exposed to high levels of thyroid hormone. More common in women (3 in 1,000 women occurrence)
Drugs that may cause hyperthyroidism.
Amiodarone Iodine
Graves' dx pathophys
Autoimmune disease in which thyroid-STIMULATING antibodies are produced. They mimic TSH on thyroid tissue.
Identify adjunctive tx for hyperthyroidism
Beta blockers CCbs (control tachycardia)
Iodide mechanism of action
Blocks hormone release and inhibits thyroid hormone synthesis
How is hyperthyroidism diagnosed?
Elevated T3/T4 in the presence of decreased TSH.
Brand SSKI
Generic Saturated solution of potassium iodide (1 g/mL - delivers 38 mg iodine / drop)
Brand Tapazole
Generic methimazole
Brand PTU
Generic propylthiouracil (given in 8 hour intervals)
Brand Lugol's solution
Generic strong iodine solution
Signs and symptoms of hyperthyroidism.
Heat intolerance Weight loss Weakness Palpitations Anxiety Tremor Tachycardia Moist, warm skin Weakness Eyelid lag
When a pt taking thioamides should speak to their MD.
If they have fever, sore throat, unusual bleeding, rash, ab pain, or yellowing of skin.
Monitoring of thioamides
Improvement of hyperthyroidism Perform thyroid function tests - s/sx of agranulocytosis
Thioamide drug interactions
Increases warfarin's effect
Iodide drug interaction
Lithium potentiates the antithyroid effect of iodides
List the iodides
Lugol's solution SSKI
Monitoring of iodides
Monitor for adverse events and improvement in s/sx of hyperthyroidism.
Thioamide MoA
PTU and methimazole inhibit thyroid hormone synth by preventing the incorporation of iodine into iodotyrosines & by inhibiting the coupling of monoiodotyrosine and diiodotyrosine to form T4 and T3. PTU also inhibits conversion of T4 to T3 peripherally.
List the thioamide medications
Propylthiouraci Methimazole (They have no permanent effect on the thyroid)
Which medication is preferred in hyperthyroidism in pregnancy?
Propylthiouracil (RAI contraindicated)
Adverse reaction of iodides
Rash, salivary gland swelling, metallic taste, burning of the mouth, GI distress, hypersensitivity, goiter
Toxic adenomas and MNGs pathophys
These are masses of thyroid tissue that secrete thyroid hormones independent of pituitary control.
Iodides place in therapy
Used when rapid reduction in thyroid hormone secretion desired (in thyroid storm), or to decrease glandular vascularity prior to thyroidectomy
RAI stands for
radioactive iodine