Card Set Information
What are the thyroid drugs?
Thyroid desiccated contains which thyroid hormones?
T3 and T4
Liothyronine contains which thyroid hormones?
Levothyroxine contains which thyroid hormones?
Liotrix contains which thyroid hormones?
T3 and T4
What are the antithyroid drugs?
Thioamides (methimazole and Propylthiouracil), iodides and Radioactive iodides
Which thyroid drugs are animal derived?
Which thyroid drugs are synthetic?
Animal thyroid is what ratio of T4:T3?
What are the advantages of animal thyroid hormones?
Inexpensive and natural
What are the disadvantages of animal thyroid hormones?
Variable T3 and T4
May degrade (more than synthetics in heat and light)
Variation among brands
What is the T1/2 of Liothyronine?
1 day – relatively short for a thyroid hormone
What is the composition of Liothyronine?
Pure synthetic T3
Does Liothyronine have a fast of slow OOA?
What are the disadvantages to Liothyronine?
Muliptle daily doses (2-3)
Fast, complete absorption = risk of toxicity
What are the advantages of Liothyronine?
Known amount of hormone
No antigenicity because of purity
4x more potent than T4
What is the DOA of Levothyroxine?
What is the composition of Levothyroxine?
Pure synthetic T4
Does Levothyroxine have a fast of slow OOA?
What are the disadvantages to Levothyroxine?
Different brands have different bioavailability
What are the advantages of Levothyroxine?
Known amount of hormone
Stable and pure hormone
Administer 1 X per day
Consistent blood levels, lower peak blood levels
What is the most commonly used Thyroid hormone?
Which drug is a mix of synthetic T3 and T4, but has no therapeutic advantage?
Why are Thyroid drugs not recommended for people with CV disease?
Can increase synthesis of B-receptors in the heart =increased stimulation of heart
Increases risk of CAD
What are the adverse effects of all thyroid drugs?
Palpitations, Angina, Tachycardia
Nausea, Diarrhea, Cramps
Tremors, weight loss, heat intolerance, sweating
What is the MOA of radioactive iodine in the treatment of HYPERthyroidisim?
Taken up by follicular cells of the Thyroid and decays, causing destruction of the Thyroid
What is the MOA of Iodides in the treatment of HYPERthyroidisim?
High amounts in milligrams (vs. normal in mcgs) inhibit Thyroid peroxidase
Reduce Synthesis and Release
What is the MOA of Thioamides in the treatment of HYPERthyroidisim?
Inhibit Thyroid peroxidase
Reduce T3 and T4 synthesis
What are the Thiamides?
Methimazole and Propylthiouracil
What are the advantages of Methimazole over Propylthiouracil?
Longer DOA = 1x daily dosing
What are the disadvantages of Propylthiouracil compared to Methimazole?
Multiple daily doses required
Can cause liver damage
What are Thioamides indicated for?
Normalizing thyroid function before radioactive iodine or surgical removal
What are the adverse effects of Potassium Iodide?
Arrhythmias (high K)
Confusion and tiredness
Dermatitis, rash and joint pain
Enlarged salivary glands due to local irritation
What are the advantages of Iodides, like Potassium Iodide?
Reduce size and vascularity of the gland
Change margin – make more distinguishable
Both help with surgery
What are the indications for Potassium iodide?
Short term treatment of hyperthyroidism before thyroidectomy
What hyperthyroid drug can only be used for several weeks before its inhibitory effect wears off?
What drugs should you give during a Thyroid storm?
Propranonol (reduce CV stimulation)
Glucocorticoids (CV stabilizing)
Iodides (immediate effects)
Prpylthiouracil (later effects)
What Antithyroid drug cures Hyperthyroidism?
What are the adverse effects of Radioactive Iodide?
S/S of Hypothyroidism
CI in pregnancy
What are the indications for Radioactive Iodide?
What are the advantages of Radioactive iodide?