thyroid/obesity/osteo quiz

• Drugs for Treatment of Hypothyroidism

  • Levothyroxine (Levoxyl, Synthroid)
  • Thyroid desiccated (Armour Thyroid)
• Levothyroxine


  Synthetic T4, drug of choice with long half-life
• Taking Levothyroxine


  1. Don't change meds without telling PCP

  2. Take on empty stomach with a full glass of water 30-60min before breakfast

  3. Take 4hrs apart from antacids/iron/calcium
• Levothyroxine


  • Adverse effects = hypothyroidism symptoms
  • Contraindications = hypersensitivity to thyroid hormone/products, uncorrected adrenal insufficiency, nontoxic diffuse goiter/nodular thyroid disease, acute MI
• Monitoring Levothyroxine


  1. Check TSH 6-8 weeks after dose change and every 3-6 months in year 1 and annually after

  2. Also check T4
• Thyroid desiccated


  T3/T4 from pigs, natural
• Drugs for Treatment of Hyperthyroidism

  • Radioactive iodide
  • Thioamide Drugs
• Radioactive iodide


  Sodium iodide I-131 (131I), emits beta particles destroying thyroid tissue
• Radioactive iodide


  • Adverse effects = subsequent hypothyroidism, taste loss (temporary), GI, tenderness/swelling/pain in neck, throat irritation, xerostomia, alopecia
  • Contraindications = pregnancy, breastfeeding, preexisting vomiting/diarrhea
• Thioamide Drugs


  Inhibit key steps in the synthesis of T3/T4, inhibit organification and coupling (PTU) also inhibits peripheral conversion of T4 to T3
• Thioamide Drugs


  • Adverse effects = rash, fever, arthralgias, agranulocytosis, hepatitis, nephritis
  • Contraindications = (for methimazole) breastfeeding, caution in pediatrics, hepatotoxicity, agranulocytosis
• Monitoring Thioamide Drugs


  Monitor thyroid function tests, CBC with differential, liver function tests, illness (fever, sore throat, malaise)
• Methimazole


  Thioamide drug
• Propylthiouracil (PTU)


  Thioamide drug
• Other Antithyroid Agents


  • Potassium iodide solution
• Potassium iodide solution


  Blocks thyroid hormone release and inhibits key synthesis steps, and peripheral conversion of T4 to T3. Decreases gland size and vascularity.
• Potassium iodide solution


  • Clinical uses = Graves' disease, thyroid storm
  • Adverse effects = allergic reaction, dose-related toxicity, metallic taste
  • Contraindications = pregnancy, before radioactive iodine treatment, patients with nodular goiter/adenomas
• Osteoblasts


  Bone builders
• Osteoporosis Treatments


  • Vitamins/Minerals
  • Antiresorptive Therapy
  • Anabolic Agents
• Osteoclasts


  Bone cutters
• Bone remodeling


  Relationship of vitamin D/calcium to bone
• PTH


  Parathyroid hormone stimulates calcium behaviors like secretion, reabsorption
• Calcitonin


  Decreases plasma calcium levels (opposite PTH goals)
• Sclerostin


  Inhibits osteoblast formation and function, inhibits formation of new bone and bone resorption
• Calcium citrate/Calcium carbonate


  Improves and/or sustains bone mineral density
• bisphosphonates

  
  

  Parenteral: Pamidronate, Zoledronic acid, Ibandronate

  Oral: Ibandronate and All others
• Calcium


  • Adverse effects = constipation, GI discomfort
  • Concerns = increased risk of MI when used without Vitamin D supplementation, hypercalcemia in CKD patients; decreased absorption of ciprofloxacin, fluoride, phenytoin, levothyroxine, and tetracycline
• Levothyroxine medication administration

  1. Take with 6 to 8 ounces of water at least 30 to 60 minutes before food, drink, or other medication

  2. Sit upright for 30 minutes after
• Calcium citrate


  Does not require acidic environment
• Calcium carbonate


  Requires acidic environment
• Vitamin D3 (cholecalciferol)


  Synthesized by body via UV, obtained via diet
• Oral bisphosphonate administration


  1. Take on empty stomach

  2. Sit up for 30 minutes after

  3. Take with 6-8oz of water
• Nasal calcitonin administration


  Administer to ONE nostril and alternate nostrils each day
• Vitamin D2 (ergocalciferol)


  Does not naturally occur in humans
• Risedronate is the oral bisphosphonate that is not required to be taken on an empty stomach
• Appropriate treatment options for osteoporosis

  • Reassess fracture risk in 2-4 years (low risk)
  • Reassess fracture risk in 2-4 years or start bisphosphonate (moderate risk)
  • Start bisphosphonate, denosumab, teriparatide or abaloparatide (high to very high risk)
• Vitamin D


  Stimulates calcium transport in the intestines and resorption in bones and tubular reabsorption in the kidney, suppresses PTH secretion/synthesis
• Romosozumab


  • Can cause MI, stroke, CV death so no in pts w stroke/MI in last 12mo, stop if pt has stroke/MI while taking
  • Normally given to postmenopausal women that are a high risk for fracture
• Duration of therapy


  1. Bisphosphonates: Reevaluate after 5yrs of use, 3yrs IV, 5yrs oral

  2. Teriparatide: 2yr limit

  3. Others can be continued for as long as clinically appropriate, review annually
• Drug holiday


  • After 5yrs in moderate-risk pts, and after 6-10yr in high risk pts
  • While in drug holiday, pt can take teriparatide/raloxifene if high-risk
  • Determine the duration of the holiday based on pt needs/circumstances