Pharm

Oral Calcium

search

Oral Calcium, Calcium Supplementation, Dietary Calcium, Calcium Carbonate, Calcium Citrate, Calcium Phosphate

  1. Starting in childhood and adolescence preferable
  2. Begin at 35-40 years old if not already started
  3. Potentiates Estrogen Replacement Therapy
  • Precautions
  1. Calcium Supplementation in Osteoporosis Prevention benefits may not outweigh cardiovascular and Nephrolithiasis risks
  2. Prevention of Hip Fracture with Calcium Supplementation Number Needed to Treat (NNT)
    1. Adults living in the community: 1000
    2. Older persons: 302
    3. Nursing Home resident: 111
  3. References
    1. Avenell (2014) Cochrane Database Syst Rev (4):CD000227 [PubMed]
    2. Lesser (2015) Am Fam Physician 91(9):634-8 [PubMed]
  • Adverse Effects
  1. Nephrolithiasis
    1. Hypercalcemia does cause Nephrolithiasis
    2. However, Calcium Supplementation is often used in normocalcemic patients with Hypercalciuria
  2. Cardiovascular disease risk (mixed evidence)
    1. CAD Risk not increased at standard Calcium dose (but may be increased at high dose >1500-2000/day)
    2. Bolland (2008) BMJ 336(7638):262-6 [PubMed]
    3. Chung (2016) Ann Intern Med 165(12): 856-66 +PMID:27776363 [PubMed]
  • Dosing
  • Calcium daily requirements
  1. Calcium is best absorbed in doses of 500 mg or less
  2. Dietary Calcium is better absorbed than Calcium in supplements
    1. Only one third of Oral Calcium supplements are absorbed, while Dietary Calcium aborption may approach 45%
    2. Calcium absorption varies considerably, and is highest in infants, and declines after age 40 years old
  3. Do not exceed Calcium 2500 mg/day in men or 2000 mg/day in women (Hypercalcemia risk)
  4. Daily dose of 1000 mg Calcium Indications
    1. Men and women ages 25 to 50 years
    2. Men 50 to 65 years
    3. Women on Estrogen Replacement ages 50-65 years
  5. Dose 1200 to 1500 mg Calcium Indications (some guidelines recommend 1000 mg daily for these groups)
    1. Ages 11 to 24 years
    2. Post-menopausal women not on Estrogen Replacement
    3. Age over 65 years
    4. Pregnancy
    5. Lactation
  • Preparations
  • Dietary Calcium Sources (300 mg elemental Calcium in each) - Preferred Source
  1. Yogurt or frozen yogurt 8 ounces
  2. Calcium-Fortified Orange Juice 8 ounces
  3. Milk 8 ounces
  4. Firm Cheese 1 to 1.5 ounces
  5. Canned Sardines 3 ounces
  6. Cooked greens, collards, or mustard 1-2 cups or 8 oz
  • Preparations
  • Calcium Carbonate
  1. Advantages
    1. Most elemental Calcium (40%)
    2. Tablet 650 mg contains 250 mg elemental Calcium
    3. Least expensive Calcium preparation
  2. Disadvantages
    1. Only 35% of Calcium supplements are absorbed (contrast with much better Dietary Calcium absorption)
    2. Constipation
  3. Administration
    1. Take with meals or citrus juice
    2. Absorption reduced with Fasting or achlorhydria
  4. Preparations
    1. Tums 500 mg orall daily to three times daily
  • Preparations
  • Calcium Citrate
  1. Advantages
    1. No Constipation
    2. Better absorption than Calcium Carbonate by >20% especially in low gastric acid state
      1. Sakhaee (1999) Am J Ther 6(6):313-21 [PubMed]
  2. Disadvantages
    1. Only 21% elemental Calcium
  3. Indications:
    1. Constipation or gas on Calcium Carbonate
    2. Calcium based Kidney Stones
    3. Gastric acid suppression medications (Proton Pump Inhibitors, H2 Blockers)
    4. Elderly patients
  4. Administration
    1. Take on an empty Stomach
  • Preparations
  • Calcium Phosphate
  1. Advantages
    1. No Constipation
    2. Absorption: 39%
  2. Disadvantages
    1. Cost
  • Preparations
  • Other Formulations
  1. Calcium Gluconate (9% elemental Calcium)
  2. Calcium lactate (13% elemental Calcium)