For women who suffer with osteoporosis, the news is good: A new medication promises to revolutionize treatment for the bone-thinning disease, particularly in women with the most severe problems.

The drug, a synthetic version of human parathyroid hormone called PTH, works by helping the body build new bone—even after dramatic loss has occurred.

New Drug Actually Helps Build New Bone

"Unlike other treatments for osteoporosis, which can help stop bone loss, parathyroid hormone actually helps the body build new bone, so that a woman has a chance to put back what her skeleton has lost over time to osteoporosis," says endocrinologist Dr. Loren Wissner Greene, co-director of the Bone Density Center at New York University Medical Center.

Although most of us stop growing in height in our late teens, our skeleton actually remains a work in progress for most of our lives, continually breaking down and re-building bone mass at a fairly steady rate.

When osteoporosis sets in, however, bone loss begins to occur faster than the rebuilding process can take place. And that means instead of being strong and solid, bones become porous, filled with little holes or craters.

As the disease progresses, there is less bone "mass" and more bone "holes"—turning a strong skeleton into one that can be weak and vulnerable.

For women, who comprise the vast majority of persons with osteoporosis, the problems generally become extremely apparent after menopause, a time when levels of the hormone estrogen drop dramatically.

Why Is This Important?

Estrogen helps to regulate factors involved in bone formation, Greene says. When estrogen levels fall, so does the production of new bone cells, she adds.

For women who start out with less bone mass to begin with, even a tiny loss can spell trouble.

"The end result can be weaker bones, and a dramatically increased risk of fracture, particularly of the hip, spine and wrist," says Greene.

Facts About Osteoporosis

There are 10 million Americans who have osteoporosis, eight million of whom are women. According to the National Osteoporosis Foundation, another 34 million women have low bone density, which is a precursor to osteoporosis.

Although there are a variety of medications available to treat osteoporosis, they all work in pretty much the same way -- to stop the bone loss.

PTH, however, stimulates new bone cell production. The results, according to endocrinologist Dr. John Adams, are nothing short of astounding.

"This drug is remarkable in the fact that while all of the other [osteoporosis] drugs are designed to inhibit bone loss, this is completely different in that it stimulates the bone forming cell, the osteoblast," says Adams, the director of the endocrinology, diabetes, and metabolism division at Cedars-Sinai Medical Center in Los Angeles.

When combined with drugs that stop bone loss, like Fosamax (aldendronate), parathyroid hormone becomes the ultimate way to increase skeletal strength, Adams says.

Drug Receives Physicians' Support

"I'm planning on putting every single one of my patients on this medicine as soon as it becomes available. I feel that strongly about it," says Adams.

As good as it sounds, there are some caveats to consider. First, the drug must be injected daily, which could be problematic for some women.

More important, however, while human trials as long as 20 months showed no serious side effects, a rat study found parathyroid hormone has the potential for causing an extremely rare but life-threatening form of bone cancer.

Although the rats received doses far above the human equivalent and were treated with the drug for an entire lifetime, the US Food and Drug Administration (FDA) was concerned enough to request that the manufacturer, Eli Lilly, conduct studies on larger animals using dosages equal to that proposed for humans.

Those results are expected soon and all indications are the drug will be considered safe enough to get the FDA's nod of approval.

Other Treatment Options For Osteoporosis

Until then, Greene says another new treatment option is Evista (raloxifene), a medication known as a SERM, or selective estrogen receptor modulator.

Often referred to as a "designer estrogen," SERMs work on a variety of diseases "by offering the benefits of estrogen without the side effects of estrogen replacement therapy, such as increased risk of breast and uterine cancer," says Wissner Greene. In osteoporosis, Evista works much like estrogen to help ensure that bone production is not outpaced by bone loss.

Also available are drugs known as bisphosphonates -- medications such as Fosamax, Didrocal (Etidronate), and Actonel (risedronate). They work specifically to slow down bone loss. Although they can be hard on the gastrointestinal tract, a new intravenous form is being tested, with a one-time treatment offering protection for up to a year.

A third alternative is the drug Miacalcin (calcitronin), a synthetic version of a hormone made in the thyroid gland that is involved in the breaking down of old bone cells. Available as a nasal spray, it also works to reduce the rate of bone loss.

A Natural Approach To Preventing Bone Loss

Finally, for those who wish to take a more natural approach, boosting vitamin D intake along with 1,500 mg of calcium daily is the way to go.

What can also help: Weight-bearing exercises such as brisk walking, which can increase the production of new bone.

Always consult your physician for more information.