Medications

Medications

Major drug therapies now exist for treating osteoporosis. Unfortunately, studies continue to report that doctors fail to evaluate and adequately treat both men and women for this condition, even after a fracture. In a 2002 study of Caucasian women over age 60, fewer than 2% were evaluated for osteoporosis or spinal fracture by their doctors. Among those who were diagnosed, only 36% received appropriate medication. Two studies in 2003 further reported that among adults who had sustained fractures, less than 5% of men and fewer than half of women were evaluated and treated according to recommended guidelines. In one of the studies, only 24% of women were given treatments for osteoporosis after a fracture. In both studies, the older a woman was the less likely she was to have adequate evaluation or treatment.

Drugs Used to Treat Osteoporosis. There are two types of drugs used to treat osteoporosis:

• Antiresorptive Drugs. Antiresorptives include bisphosphonates, hormone replacement therapy, SERMs, and calcitonin. Bisphosphonates are the standard drugs used for osteoporosis. These drugs block resorption (bone break down) and so slow the rate of bone remodeling, but they cannot rebuild bone. In fact, because resorption and reformation occur naturally as a continuous process, blocking resorption may eventually also reduce bone formation.
• Anabolic, or Bone-Forming, Drugs. Drugs that rebuild bone are known as anabolics. The primary anabolic drug is low-dose parathyroid hormone (PTH), which is administered as injections. It is proving to be very effective in restoring bone and preventing fractions. PTH is still relatively new, and long-term effects are still unknown. Fluoride is another bone-building drug, but it has limitations and is not commonly used.

Both types of drugs are effective in preventing bone loss and fractures, although they vary in their effectiveness and safety.

Bisphosphonates

Bisphosphonates are anti-resorptive drugs. That means they prevent bone breakdown. They are now the primary drugs for preventing and treating osteoporosis. They can help reduce the risk of both spinal and hip fractures, including in patients who have had prior bone breaks.

Studies indicate that these drugs are effective and safe for at least 10 years. Eventually, however, bone loss progresses with bisphosphonates. This may be due to the fact that bone breakdown (resorption) is one of two phases in a continuous process of bone resorption and reformation. Over time, just blocking resorption will interrupt this process and impair the second half of the process -- bone formation. Some experts think that this problem may be overcome by building bone for a couple of years with parathyroid hormone (PTH), then following this treatment with bisphosphonates to prevent the breakdown of bone. (Administering the two drugs simultaneously is not effective because bisphosphonates interfere with the way PTH works.)