Dear Dr. SerVaas: I have advanced osteoporosis. Could you share any knowledge you have with readers (and possibly my doctor) on the relatively new drug called Forteo?I understand that it is given by injection once a month. I, and probably others with stomach problems, would welcome another means of absorbing osteoporosis medication.

Margaret Callis
Grand Rapids, Michigan

Dear Reader: Forteo, a synthetic form of parathyroid hormone developed by Eli Lilly and Company, is injected daily. Data show that the first-of-its-kind drug increased bone density nine percent and reduced fractures by 60 to 70 percent in men and postmenopausal women.

Bone is a complex structure composed of minerals and cells that dissolve old bone (osteoclasts), as well as other cells that replace it with new, healthy tissue (osteoblasts).

Most current therapies for osteoporosis slow bone breakdown by osteoclasts and produce some bone repair. Skeletal anabolics such as Forteo (generic name: teriparatide) build new bone by increasing the number and action of osteoblasts. The FDA is evaluating research findings on other drugs in the class.