There are many bisphosphonates that have been approved by the FDA for use in America, and are also used in Europe. One of these is Fosamax; this is alendronate sodium and is manufactured by Merck. It acts by mimicking the natural occurring pyrophosphates that are involved in the inhibition of bone resorption.
Fosamax is an FDA approved form of alendronate that has been shown to reduce the fractures in hips, the spine and wrists by half when used over a three year period in people who have already suffered a spine fracture. In people who have no history of spine fractures the decrease in spine fractures that occurs over a three year period in comparison to people not taking osteoporosis treatments is 48%.
Fosamax is often taken at a dose of 5mg per day (35mg weekly) if used in the prevention of osteoporosis fractures. When Fosamax is being used for the treat osteoporosis fractures then Fosamax is usually taken at a dose of 10mg per day (70mg weekly) with a supplement of vitamin D.
Fosamax is usually taken orally and the tablet form needs to be took with a glass of water; if taken alendronate sodium as a solution then it should be washed down with a little water. It is best to take the treatment in the morning, and it should never be taken before retiring to sleep. Additionally it is important that people who take the treatment remain in an upright position and refrain from taking food for 30 minutes or longer following taking Fosamax. Although Fosamax can be taken by people who have a mild renal insufficiency it should not be taken by people who have severe renal insufficiency.
Research carried out on post menstrual women that looked at the effect of alendronate sodium on the incidence of bone fractures as shown positive results. The women were given a supplement of calcium and vitamin D, and either alendronate sodium or a placebo. It was found that there was an increase in bone mineral density and a reduction in rates of total fractures by about 14%. The use of alendronate sodium led to a reduction of neck fractures by around 36% in women with osteoporosis and a reduction of 44% was seen when accessing vertebral fractures. If patients did not have osteoporosis and hence had a healthy bone mineral density then no significant reduction was seen when taken Fosamax in comparison with the placebo.
The use of Alendronate sodium can help to increase bone mineral density in osteoporosis sufferers (people with a BMD t-score of -2.5 or less) and lead to a reduction in the risk of fractures in osteopenia and osteoporosis sufferers with a BMD T-score of -2 or less.
However there are many known side effects when taking bisphosphonates such as Fosamax, these are discussed in other sections of the osteoporosis advice site.
References
Mayes (2007) Review of post menopausal osteoporosis pharmacology. Nutr. Clin. Prac. 22:3: 276 to 285
Cummings et al (1998). Effect of alendronate risk of fracture in women with low bone density but without vertebral fractures: results from the Fracture Intervention Trial. 2077 to 2082.