Dear Dr. Donohue: 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?

- J.G.

A: Three hundred thousand hips, 700,000 vertebrae and 250,000 wrists are broken yearly in the U.S., and osteoporosis is the major cause of these breaks, especially in older people. Osteoporosis, therefore, is a major health problem and a major cause of disability and medical expense.

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.

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." The doctor can determine a person's risk for fracture by using an Internet program called FRAX (www.

shef.ac.uk/FRAX), devised by the World Health Organization. If someone is at high risk for a fracture, the FRAX program places the risk for a broken bone at more than 3 percent within 10 years. Those patients should stay on treatment for 10 years.

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

A reason for concern is bisphosphonates have side effects. One is osteonecrosis of the jaw, death of a section of the jawbone, a consequence that's difficule to treat. It happens only to a few, usually those taking the drug at high doses for cancer that has spread to the bone.

Don't forget people over 50 need vitamin D and calcium for osteoporosis prevention. Daily exercise is essential.

Dr. Paul Donohue writes for North America Syndicate. Send letters to Box 536475, Orlando, FL 32853-6475.

Step by step

Dear Dr. Donohue: What is the best treatment for Morton's neuroma?

- V.L.

A: People with a Morton's neuroma feel as if 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. The involved nerve is at the front of the foot, on the sole, just behind the toes. 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.

Donation frequency

Dear Dr. Donohue: How long after a blood donation should a person wait before giving a second donation? A friend of mine gave blood, and two months later donated more blood. The second donation took place at an event where a Cancer Walk was taking place. A special van for blood donation was there. I waited and waited for my friend to come out of the van. It seemed as if she was there forever. It turns out her blood pressure was low, and the blood people decided to let her rest for a while.

- D.S.

A: It's acceptable to donate blood again two months after the first donation. The drop in her pressure didn't last long and won't have any health consequences.

Ubiquitous bacterium

Dear Dr. Donohue: What is pseudomonas? Is it catchy? What does it cause?

- L.P.

A: Pseudomonas (SUE-duh-MOE-niss) is a bacterium found just about everywhere - on plants, on animals, in soil and sometimes on human skin. It often lives in peace with us. However, it can cause skin infections, pneumonia, urinary tract infections and many more. It's a germ that is mostly unaffected by the commonly used antibiotics. Special ones do exist for its treatment.