Reader is in gray area of treatment

Dear Dr. Roach: I took Fosamax for years but stopped five years ago.

My bone density score is now -2.5. Should I restart Fosamax?

If it creates more mass of brittle bone, then it does not seem advisable. — K.B.

Fosamax (alendronate) works by preventing absorption of bone by osteoclasts (bone-absorbing cells).

When used for three to five years, it improves bone density and reduces the risk of fracture.

However, when used for longer periods, it can cause brittle bone, as you have said, and can put people at risk for “atypical” fractures of bone, especially the femur.

You are in a situation has no definitive answer.

Your bone density is at a level where it might be appropriate to re-treat.

However, there is more to fracture risk than just the bone density score, so I would recommend a FRAX test (available at https://www.sheffield. ac.uk/FRAX/tool.aspx ?country=9).

If your FRAX score indicates a 10-year risk of a hip fracture of 3 percent or greater, or if your 10-year risk of combined major osteoporotic fracture is at least 20 percent, treatment would be recommended.

Some experts would use a bisphosphonate like Fosamax again, because after five years off treatment, an atypical fracture is not likely.

However, others would use a different type of treatment, such as teriparatide, which works by stimulating new bone growth.

There are no studies to guide treatment in your situation, so the clinical experience of your treating provider is key.

Since you are concerned about brittle bone, I might prefer teriparatide for a person in your situation. that