Thyroid and parathyroid agents Flashcards
Chapter 37
What does the thyroid gland produce?
-Thyroxine(T4)
-Tri-iodothyronine(T3)
-Calcitonin
-Regulates metabolism
-Requires iodine to produce needed substances
-Production and release regulated by TSH
TSH regulated by TRH
What are the functions of the thyroid?
-Carbohydrate and lipid metabolism
-Growth and development
-Heat regulation
-Cardiac regulation
-Neuromuscular function
What is hypothyroidism?
-Lack of sufficient thyroid hormone
-Lack of necessary iodine
-Tumor or auto-immune disease
-Pituitary or hypothalamus disease
-Radiation to thyroid
-Surgery
-LowT4 and elevated TSH
What are disease that are caused by hypothyroidism?
-Myxedema- often gradual
-Hashimotos disease-autoimmune
-Treat with replacement of thyroid hormone therapy
suppresses overproduction of TSH
**Treatment of hypothyroidism
What is levothyroxine (Synthroid, Levothroid, Levoxine)
-Common drug treatment for hypothyroidism
-Synthetic T4
What are contradictions when taking levothyroxine (Synthroid, Levothroid, Levoxine)?
**Treatment of hypothyroidism
-Allergy
-During thyrotoxicosis, acute myocardial infraction
What should cautions be when taking levothyroxine (Synthroid, Levothroid, Levoxine)?
**Treatment of hypothyroidism
-Lactation because it can enter humans milk and could suppress infants thyroid production
- Monitor for hyper thyroidism
-Hypoadrenal conditions like addisions cause body will not be able to deal with drug effects
-caution with older adults because they will require low doses to become euthyroid
What are nursing concerns with thyroid replacement medication?
-Assess cardiovascular status, may need med adjustment
-Assessment for overdose (hyperthyroidism)
-Take regularly in AM, empty stomach
-May need diabetic med adjustments
-Oral anticoagulant effect increased
-Decrease effectiveness of digitalis
-Periodic blood tests for thyroid function
-Older adults ─ screen for co-morbidities, start low
-Pregnancy ─ does not cross placenta, caution with lactation
-Children ─ levothyroxine used
Describe hyperthyroidism
-Excessive amounts of thyroid hormone produced and circulated
-Goiter which can happen due to increase of thyroid
-Graves disease (autoimmune dz) ─ over production of thyroid hormone, most common cause of hyperthyroidism
-Labs –> Low TSH and high T4
What do Antithyroid meds do?
-Block formation of thyroid hormones in thyroid gland, treat hyperthyroidism
What are drug names of anti-thyroid meds?
Thioamides
**prophylthiouricil (PTU)
**methimazole (Tapazole)
Iodine products ─ iodine needed to produce thyroid hormone, large doses block this function
-Potassium iodide
-Sodium iodine I131 -thyroid cells destroyed by radioactivity
What does Thioamides do?
propylthiouracil (PTU)
**methimazole (Tapazole)
**Anti-thyroid drugs
-Prevent the formation of thyroid hormones in the thyroid cells , which lowers the serum levels of the thyroid hormone
What are contras with Thioamides meds?
**propylthiouracil (PTU)
**methimazole (Tapazole)
**Anti-thyroid drugs
Pregnancy/lactation(develop of thyroid being mot being developed in baby)
What cautions should you have when taking Thioamides?
**propylthiouracil (PTU)
**methimazole (Tapazole)
-Monitor for over suppression of thyroid ─ lethargy, bradycardia, n/v/d
-Changes serum levels of some drugs as metabolism slows ─ anticoags, beta blockers
What are contras with Iodine solutions ?
Pregnancy
What are cautions to have with iodine solutions?
-Monitor for hypothyroidism, begin replacement therapy
-GI distress n/v/d, teeth staining with liquids
-Monitor serum levels of some drugs
Describe the parathyroid
-Gland located behind thyroid, regulates calcium levels
-Dysfunction related to absence of PTH (hypoparathyroidism) or overproduction of PTH (hyperparathyroidism)
-Leads to hyper or hypcalcemia
-Calcium *.8-10.4 mg/dl
Nerve conduction and muscle contraction
**Antihypocalcemic Agents
Deficient levels of PTH hypocalcemia
What mediation helps with these issues?
**calcitriol (Rocaltrol)-Vit. D
What is the function of calcitriol (Rocaltrol)-Vit. D?
**Antihypocalcemic Agents
-Regulates calcium absorption from small intestines
-Increases calcium levels, decreases phosphorous
What are contras of calcitriol (Rocaltrol)-Vit. D?
**Antihypocalcemic Agents
Allergy, hypercalcemia
What are cautions to have with calcitriol (Rocaltrol)-Vit. D?
**Antihypocalcemic Agents
Renal stones, watch for n/v/ constipation
-Increasing calcium levels so look out for kidney stones and if thye have history of kidney sgtones they are more at risk for kidneys stones
What do Antihypercalcemic Agents do?
Drugs act on serum levels of calcium not on PTH
What is a Antihypercalcemic medication?
Bisphosphonates
**alendronate (Fosamax)
What does Bisphosphonates
**alendronate (Fosamax) do?
Antihypercalcemic
Slows bone resorption, lower serum calcium levels, does not prevent bone formation
