Strontium ranelate

Oral Strontium ranelate (Protelos/Protos/Protaxo/Osseor - Servier) is the first in a new class of drugs called a Dual Action Bone Agents (DABA's). It has proven efficacy in the prevention of both vertebral and non-vertebral fractures (including hip fracture) in patients over the age of 80, who are the most at risk where osteoporosis is concerned. Strontium Ranelate works by stimulating the proliferation of osteoblast (bone building) cells (there is some debate about this), and inhibiting the proliferation of osteoclast (bone absorbing) cells.

This means that strontium Ranelate increases BMD by forming new bone, rather than just preserving existing bone. In comparison to bisphosphonates which only act on one aspect of bone remodeling, strontium ranelate also preserves bone turnover, allowing the microarchitecture of the bone to be continuously repaired as it would in healthy bone.

Strontium ranelate is taken as a 2g oral suspension daily, and is licenced for the treatment of osteoporosis to prevent vertebral and hip fracture (this may differ by country and is not approved in the USA). Strontium ranelate has side effect benefits over the bisphosphonates, as it does not cause any form of upper GI side effect, which is the most common cause for medication withdrawal in osteoporosis.