Forteo (Teriparatide) increases the thickness of the struts making up spongy (cancellous) bone. Forteo is the only osteoporosis medication to do that. It also makes the hard outer shell (cortical bone) thicker. How? Forteo stimulates OsteoBlasts. They make bone matrix, the collagen protein that is more than 80% of bone.
Forteo also stimulates bone turnover. Healthy bone is constantly being resorbed and replaced. This allows bone to eliminate the micro-cracks that gradually accumulate with activity. Bone is strongest when it is a mixture of older more calcified (stiffer) material mixed thoroughly with younger less calcified (somewhat bendable) material. Cracks cannot enlarge. Strength is better. More force is required to fracture the bone.
The Anabolic, Forteo, increases OsteoBlast function (bone formation) by 200%. OsteoClast function (bone resorption) increases by 50%. The result is increased bone turnover for healing stress fractures and other cracks, and increased bone volume.
The increase in spongy (cancellous) bone volume and connectivity is very impressive. I have seen this when doing a second Total Knee Replacement after adding Forteo because the bone was so fragile in the first knee operated.
Forteo must be followed by an Antiresorptive in order to preserve the gains made. You can lose all the gains made with 2 years of Forteo in 2 to 3 years if you do not get Antiresorptive medication to follow the Anabolic medication. It is tragic that the FDA forbids the manufacturer’s employees and spokespersons from mentioning this critical information proactively. I have personally seen patients harmed because their doctors were not told this crucial information.
If you need to increase your cancellous bone, consider the Anabolic, Forteo.
Jay Ginther, MD