- Calcium carbonate must be taken with meals because it requires an acidic environment for absorption.
- Calcium citrate may cause fewer gastrointestinal side effects, such as constipation.
Because one-time calcium absorption is limited to <600 mg, multiple daily dosing is required. The National Osteoporosis Foundation recommends >800 IU of vitamin D daily to reduce fracture risk in patients age >50 and in those with osteoporosis.7
Bisphosphonates have been shown to reduce fracture risk and increase bone mineral density, primarily in the spine and hip and sometimes within 6 months. Once-weekly alendronate and once-monthly risedronate and oral ibandronate are FDA-approved for prevention and treatment of osteoporosis in postmenopausal women. Quarterly ibandronate and once-yearly zoledronic acid injections are approved for osteoporosis treatment. Alendronate and risedronate also are approved to treat osteoporosis caused by glucocorticoid therapy and in men.
Although bisphosphonates do not cause adverse psychiatric effects or interactions with psychotropic medications, bisphosphonates must be taken at least 30 minutes before any other medications. Adverse effects from oral bisphosphonates often are gastrointestinal—such as nausea, heartburn, pain, irritation, and ulceration—and patients should take these medications with only a glass of water and remain upright for at least 30 minutes after ingestion.
Other therapeutic options include teriparatide—a synthetic form of parathyroid hormone injected daily—calcitonin, and raloxifene. Estrogen therapy increases bone density in postmenopausal women but is not recommended for routine use because of increased risk of stroke, thromboembolism, heart disease, and breast cancer.
Related resources
- World Health Organization Fracture Risk Assessment tool. www.shef.ac.uk/FRAX.
- National Osteoporosis Foundation. www.nof.org.
Drug brand names
- Alendronate • Fosamax
- Calcitonin • Miacalcin
- Ibandronate • Boniva
- Lithium • various
- Phenobarbital • various
- Phenytoin • Dilantin
- Prednisone • Deltasone, Meticorten
- Raloxifene • Evista
- Risedronate • Actonel
- Teriparatide • Forteo
- Valproic acid • Depakene
- Zoledronic acid • Reclast
Disclosure
The authors report no financial relationship with any company whose products are mentioned in this article or with manufacturers of competing products.