Q: I am very worried about being taken off Fosamax. I have osteoporosis and have taken Fosamax for 11 years. My doctor said I don't need to take it any longer because my system has enough of it. I thought I had to be on this all my life. I am 79. Would you give me your opinion on this?

A: Bisphosphonates are the class of drugs most often chosen to slow down osteoporosis. Fosamax (alendronate) is an often-prescribed bisphosphonate. It stops the daily breakdown of bone, and thereby strengthens bone. This action prevents bones from becoming fragile and easily broken.

How long is it necessary to take these drugs? That's a question without a current answer. One approach to treatment is to suggest to patients that they take a drug holiday after five to seven years of use. This suggestion is made to patients who have a "low fracture risk."

Fosamax and other bisphosphonates stay in bone for years, so you are still getting medicine after you have stopped taking it. When medicine is stopped, doctors follow their patients with scheduled bone mineral density tests to see if their bones are developing osteoporosis. If they are, the medicine can be resumed or a different one prescribed.

Bisphosphonates have side effects. One is osteonecrosis of the jaw. Osteonecrosis is death of a section of the jawbone, a consequence that's hard to treat and difficult to have. It happens only to a few, and then mostly to those who

Don't forget that people older than 50 need vitamin D (up to 1,000 IU a day) and calcium (up to 1,200 mg a day) for osteoporosis prevention. Daily exercise is also essential.

Q: What is the best treatment for Morton's neuroma? Surgery or cortisone injection?

A: People with a Morton's neuroma feel like they're stepping on a stone each time the affected foot hits the ground. Or the neuroma causes burning or shooting pain with each step. The neuroma is a foot nerve trapped in dense scar tissue. Most often, the area of the foot that corresponds to the space between the third and fourth toes is the site for a Morton's neuroma. As a first treatment, try padding. Metatarsal pads can be found in almost all drugstores. If they fail, specially constructed shoe inserts, orthotics, should be used; then a cortisone injection. The final step is surgical freeing of the entrapped nerve.

Dr. Paul Donohue appears Mondays. Write to him at P.O. Box 536475, Orlando, FL 32853-6475.