In patients with established osteoporosis, therapies that are available include drugs that inhibit bone resorption, namely calcitonin, bisphosphonates and oestrogen. All of these drugs probably have similar efficacy, although this is still debated.
Their effects on bone formation are probably much less prominent than their effects on bone resorption. Attempts to stimulate bone formation over prolonged periods in patients with osteoporosis are still experimental. Fluoride increases bone mass, although it may also increase propensity to fracture. Low- dose PTH has an anabolic effect on the skeleton to increase bone mass, although this effect may not be maintained; this drug is still investigational.
