Medication Options in the Prevention and Treatment of Osteoporosis

Calcium and Vitamin D Supplementation

Most people will build the majority of their bone, often called "bone mass," by the age of 20. Some additional bone may be added until about the age of 32. These are the times when ‎plenty of calcium are most important. However, even after the age of 32, continuing to take calcium has been ‎shown to be beneficial in preserving existing bone mass.

Recommended Amounts of Daily Calcium

Teens and young adults 11-24 years: 1,200-1,500 milligrams

Women 25-50 years: 1,000 milligrams

Postmenopausal women on estrogen: 1,000 milligrams

Postmenopausal women not on estrogen: 1,500 milligrams

Pregnant and breastfeeding women: 1,200 milligrams

Men 25-50 years: 1,000 milligrams

Men and women 65 years and older: 1,500 milligrams

Note: Over-supplementation with calcium can be harmful, so don't overdo it!

Only 500 milligrams of calcium can be absorbed in the stomach ‎at one time, so it is recommended to divide up your calcium intake throughout the day. For calcium to be ‎absorbed, adequate vitamin D is also needed. The recommended amount of vitamin D is 400 IU per day ‎for healthy adults. Calcium and vitamin D intake is important even if you are taking other medications for ‎bone loss.‎

Prescription Medicines

Prescription medications are most commonly used:

• When a person is diagnosed with osteoporosis.
• When hormone replacement therapy has been stopped.
• When there is severe enough bone loss to warrant drug therapy.

Bisphosphonates

Bisphosphonates are a class of drugs that inhibit the breakdown of bone. These drugs have also ‎been found in studies to increase existing bone mass. The two drugs in this class include alendronate (trade name: Fosamax) and risedronate (trade name: Actonel). Possible side effects of these drugs include: gastrointestinal problems and ‎severe heartburn.

However, to prevent these side effects from occurring, these drugs should be taken in the morning ‎before eating or drinking anything. They should also be taken with a full glass of water. You should avoid ‎lying down and eating or drinking anything for 30 minutes after taking the medication. For ease of ‎administration, a once-weekly formulation is available in both agents. While most patients remain on these ‎medications indefinitely, your physician will determine the duration for your specific needs.‎

Selective Estrogen Receptor Modulators (SERMs)‎

Raloxifene (trade name: Evista) is currently the only medication in this class to be approved for the ‎prevention and treatment of postmenopausal osteoporosis. This drug works similar to estrogen in ‎preventing bone loss; however, it doesn't affect areas that estrogen may adversely affect such as the breast ‎and uterus. This makes raloxifene a good choice for patients who cannot take estrogen due to a history of ‎breast cancer, but still wants the positive effects on bone mass that estrogen can provide.

One side effect ‎that is commonly reported with raloxifene is hot flashes, which may be bothersome for patients already ‎experiencing hot flashes due to menopause. The dose of raloxifene is 60 milligrams a day, and as with the other ‎medications, the length of time on this drug would be up to your physician.‎

Calcitonin

Calcitonin is available as both an injection and as a nasal inhaler (trade name: Miacalcin). In studies, nasally ‎administered calcitonin has been shown to decrease the number of vertebral fractures and increase bone ‎density in postmenopausal women.

Common side effects of the nasally administered formulation include ‎nasal irritation, inflammation of the nasal mucosa, and nose bleed. Injectable calcitonin has only been ‎proven in clinical trials to increase bone density. There is no information on the decreased incidence of fractures is ‎available. The nasal spray formulation is used to provide optimal absorption of the drug into the ‎bloodstream. Miacalcin may also be the treatment of choice for patients who cannot take oral ‎medications.

Parathyroid Hormone Derivatives

The Food and Drug Administration has recently approved the use of teriparatide (trade name: Forteo) ‎for the treatment of osteoporosis in patients with severe osteoporosis or those who are no longer responding ‎to other therapies. Teriparatide is a parathyroid hormone derivative, and it is the first agent approved that ‎stimulates new bone formation. It is available in a subcutaneous injection that is administered in the thigh ‎or abdomen.

During clinical trials, teriparatide use resulted in fewer fractures among postmenopausal ‎women, with only mild side effects such as nausea, dizziness, and leg cramps occurring. There is potential ‎for an increased chance of developing osteosarcomas, a type of bone cancer, with teriparatide use. However, this increased risk has only been noted in animals. Due to the unknown long-term effects of ‎teriparatide, therapy for longer than two years is not recommended at this time.

References

1. Schuna, A.A. and Dong, B.J.. Teriparatide Provides Useful Option in Severe Osteoporosis. Drug Information ‎Line; American Pharmaceutical Association. December 2002; 3.

2. Managing Osteoporosis: Clinical Challenges in Primary Care. Continuing Education Program; ‎American Medical Association. December 2002.‎