Chapter 31: Thyroid and Anti-Thyroid Test, Iodine, Pharmacology for Nurses: Practical Apps
The key terms in this Pharmacology course include Thyroid and anti-thyroid, Iodine, Patient, Radioactive Iodine (I-131) Therapy, Pharmacology for Nurses: Practical Applications
Which patient statement demonstrates understanding of radioactive iodine (I-131) therapy?
“I will need to take this drug on a daily basis for at least 1 year.”
“I will isolate myself from my family for 1 week so there is no risk of radiation exposure.”
“This drug will be taken up by the thyroid gland and destroys thyroid tissue.”
“This drug will help decrease my cold intolerance and weight gain.”
Radioactive iodine is an antithyroid medication that is administered orally. It concentrates in the thyroid gland, where its radioactivity destroys thyroid tissue.
When assessing for potential serious adverse effects to propylthiouracil (PTU), the nurse will monitor which laboratory test?
Serum electrolytes
Complete blood count (CBC)
Kidney function
Brain natriuretic peptide
With antithyroid medications, the nurse should monitor for possible serious adverse reactions such as agranulocytosis, leukopenia, and thrombocytopenia. These would be present in a complete blood count (CBC) as abnormal values and indicate bone marrow dysfunction.
A patient is being prescribed levothyroxine for the first time. Which statement by the patient indicates an understanding of discharge instructions given by the nurse?
“I will take this medication in the morning so it does not affect my sleep at night.”
“I can expect improvement of my symptoms within 1 week.”
“I will take a double dose to make up for the missed one.”
“I will stop the medication immediately if I feel pain or weakness in my muscles.”
Levothyroxine increases basal metabolic rate and thus may cause insomnia. Patients should not double the dose or stop taking the medication abruptly. It may take up to 4 weeks for a therapeutic response to occur.
The nurse would suspect a patient is taking too much levothyroxine when the patient exhibits which adverse effect?
Irritability
Weight gain
Feeling cold
Lethargy
Irritability is a symptom of hyperthyroidism and may indicate toxicity of the medication. The other choices are signs of hypothyroidism.
The nurse is reviewing the adverse effects of antithyroid medications for a patient prescribed propylthiouracil (PTU). What potential serious adverse effects would the nurse discuss with the patient during discharge teaching? (Select all that apply.)
Liver toxicity
Joint pain
Bone marrow toxicity
Increased urination
Kidney damage
The most damaging or serious adverse effects of the antithyroid medications are liver and bone marrow toxicities. Myalgias and arthralgias (joint pain) may also occur with PTU.
The nurse is teaching a patient taking an antithyroid medication to avoid food items high in iodine. Which food item would the nurse instruct the patient to avoid?
Milk
Seafood
Eggs
Chicken
Seafood contains high amounts of iodine and should be avoided. The other options do not contain high amounts of iodine.
A patient receiving propylthiouracil (PTU) asks the nurse, “How does this medication relieve symptoms?” What is the appropriate response by the nurse?
“PTU inhibits the formation of new thyroid hormone, thus returning your metabolism to normal.”
“PTU helps your thyroid gland synthesize and use iodine, which produces hormones better.”
“PTU causes the pituitary gland to secrete thyroid-stimulating hormone, which blocks the production of hormones by the thyroid gland.”
“PTU removes thyroid hormones that are already circulating in your bloodstream, thus decreasing the adverse effects of this medication.”
PTU is an antithyroid medication used to treat hyperthyroidism. It works by inhibiting the synthesis of new thyroid hormone. It does not inactivate present hormone.