Pharmacological Treatments for Osteoporosis
Patients meeting criteria for osteoporosis (T-score below 2.5) or other high risk patients with a history of osteoporotic fracture gain significant benefit from treatment. Therapy should be initiated in these patients.
Consideration of drug therapy in postmenopausal women with fragility fractures and low bone mineral density, women who meet the criteria for osteoporosis, women with a T-score below 1.5 in the presence of risk factors, and women who continue to experience bone less or fragility fractures despite non pharmacological treatments.
When elemental calcium supply is insufficient calcium is taken from the bone stores to maintain the serum calcium level. Calcium plays an important role in maximizing peak bone mass and decreasing bone turnover and slowing bone loss.
Factors can limit elemental calcium absorption: large amounts of calcium taken at once cannot be absorbed. Supplement doses should be limited to 500 to 600mg of elemental calcium per dose. Calcium intake greater than 2500mg/day should be avoided due to increased risk of toxicity including hypercalciuria and hypercalcemia.
One pharmacological treatment is calcium carbonate and it should be taken with food to maximize absorption. Patients receiving proton pump inhibitors (PPIs) or histamine (H2) receptor antagonists may have added difficulty absorbing calcium supplements because of reduced stomach acidity. Better absorption may occur in this setting with calcium citrate because an acid environment is not needed for absorption and can be taken with or without food.
Adverse effects of increased elemental calcium supplements include constipation, bloating, cramps and flatulence.
Other important pharmacological treatments include Vitamin D. Doses above 2000IU/day should be avoided due to risk of hypercalciuria and hypercalcemia.
Vitamin D2 and D3 are available in higher doses and generally reserved for patients with a vitamin D deficiency.