Thyroid Disorders: Chapter 40
Terms in this set (16)
levothyroxine brand names
levothyroxine doses (12)
Which of the following medications can decrease the levels of levothyroxine?
magnesium-aluminum hydroxide (Maalox)
CU takes warfarin for atrial fibrillation. He has been discharged from the hospital with several new medications: levothyroxine, diltiazem and amiodarone. Select the correct statement/s.
A. addition of levothyroxine can lead to a supratherapeutic INR
B. Addition of diltiazem can decrease levels of levothyroxine and suboptimal control of hypothyroidism
C. Addition of levothyroxine will increase the patient's risk of DVT
D. Addition of amiodarone can lead to a supratherapeutic INR
E. Addition of diltiazem can lead to subtherapeutic INR
Feedback: Levothyroxine can increase the INR and a patient stable on warfarin will require monitoring of the INR when levothyroxine is added. Amiodarone causes a large increase in the INR and the clinician should decrease the warfarin dose when amiodarone is added to the regimen of a patient with a stable INR. Both drugs put the patient at increased risk for bleeding, not clotting.
propylthiouracil can have this effect on blood cells:
Both PTU and methimazole have a risk of decreasing white blood cells, including a risk of agranulocytosis. Patients should watch for signs of infection.
hyperthyroidism treatment in pregnancy (per trimester
2nd and 3rd: methimazole
Liothyronine brand name
A patient gave the pharmacist a prescription for Armour Thyroid 60 mg once daily #30. Which of the following is a correct statement/s concerning Armour Thyroid?
A. it contains both T3 and T4
B. It is not the preferred agent for hypothyroidism
C. It is not synthetic; it is derived from pork thyroid gland
D. some patients prefer it
E. It will raise the TSH
Feedback: Some patients feel better using Armour Thyroid. Levothyroxine is the preferred agent, and there is no proof that Armour Thyroid works better. Some feel that certain patients might not convert enough T4 to T3, but this is not proven. Armour Thyroid USP is manufactured according to good manufacturing practices (GMPs).
PTU and warfarin drug interaction
PTU decreases the effect of warfarin
Which of the following drugs can cause hyperthyroidism? (Select ALL that apply.)
E. Thyroid hormone taken in excess
Feedback: Lithium causes only hypothyroidism. Amiodarone and interferons can cause either hypothyroidism or hyperthyroidism.
IV to PO ratio for levothyroxine (fasting state)
IV to PO 0.75 to 1
JH is a 78 year-old female with heart failure and history of MI. She has just been diagnosed with hypothyroidism. JH is five feet tall and weighs 103 pounds. She is going to begin levothyroxine therapy. What is an appropriate starting dose for this patient?
Feedback: Patients with known CAD are started at 12.5-25 mcg/day. The patient returns in 4-6 weeks and the dose is adjusted until the TSH is normalized and symptoms have resolved. The average maintenance dose of levothyroxine for most adult patients is 100-150 mcg/day. Older patients often require less.
AA has been prescribed propylthiouracil, which should be reserved for patients who cannot use other options due to the risk of this adverse reaction
Feedback: PTU has a boxed warning for severe liver injury, which can come on suddenly, even after long-term use.
methimazole brand name
A patient with heartburn has been using OTC anti-gas and antacid products for many years. She has recently been diagnosed with hypothyroidism. Which of the following OTC medications will not interact with her thyroid medicine?
A. Magnesium Hydroxide
B. Calcium carbonate
C. Aluminum Hydroxide
E. Pepcid Complete
Which of the following statements concerning the treatment of hyperthyroidism is/are correct?
A. Graves disease can be treated with radioactive iodine, thyroidectomy, or medications
B. Beta Blockers are often used initially to control symptoms such as palpitations and racing heart beat
C. Methimazole is preferred in thyroid storm
D. Initially, higher doses of drugs are used to control symptoms; afterwards the doses of the drugs are typically decreased to prevent over-treatment and consequently, hypothyroidism
E. Patients receiving methimazole or PTU must be monitored for hepatitis.
Feedback: Propylthiouracil is preferred in thyroid storm. Patients with hyperthyroidism may have all or part of their thyroid surgically removed as a treatment option.