Alendronate

Brand names

• Fosamax

Usage

To prevent and treat osteoporosis in postmenopausal women. Also used to treat glucocorticoid-induced osteoporosis in those receiving corticosteroids, and to treat Paget's disease, a disorder characterized by rapid breakdown and reformation of bone, which can lead to bone fragility and malformation.

How it works

Healthy bones are continuously remodeled (broken down and then reformed); the minerals and other components of bones are reabsorbed by one set of cells (osteoclasts) and replaced by another set of cells to form new bone. Alendronate suppresses the activity of osteoclasts; consequently, the breakdown of bone tissue occurs more slowly than the laying down of new bone. This action preserves bone density and strength.

Side effects

Serious

No serious side effects have been reported.

Common

Abdominal pain or bloating (persistent abdominal pain should be reported to your doctor), indigestion, heartburn, nausea.

Less common

Headache, constipation, diarrhea, gas, swallowing difficulty, throat irritation, abdominal swelling or tightness, muscle or bone pain, changes in taste perception.

Possible interactions

Other medicaments:

Alendronate taken concurrently with:

• antacids may decrease the total absorption of alendronate and decrease its therapeutic benefit.
• aspirin or aspirin-containing products or salicylates may pose an increased risk of upper gastrointestinal adverse effects if more than 10 mg of alendronate is taken daily. Although other NSAIDs were not presented as potential problems with alendronate doses greater than 10 mg, caution is advised.
• estrogens (various) taken by a few women in clinical trials did not have problems. Combination not presently recommended due to lack of specific data. FACET study showed a benefit of this combination, but it is not FDA-approved.
• foscarnet (Foscavir) may result in an additive decrease in calcium.
• magnesium (various) may increase stomach/intestine upset.
• medicines in general should not be taken at the same time as alendronate. Separate any dose of alendronate and any other medicine by at least half an hour.
• mesalamine or olsalazine may increase stomach/intestine upset.
• ranitidine (Zantac) (intravenous form and perhaps oral form) may double how much alendronate gets into your body. The clinical importance of this is not yet known.

The following medicaments may decrease the effects of alendronate:



• because a small amount of alendronate gets into the body under the best conditions. Take alendronate with a full 6 to 8 ounces of water. Take any other medicaments at least half an hour after alendronate.

Foods:

Do not take this medicament with food.

Herbal medicines or minerals:

Soy or other plant-derived phytoestrogens may work to complement alendronate, but have not been studied. Ipriflavone is a synthetic flavonoid currently investigational for osteoporosis (which both inhibits bone resorption by reducing osteoclast recruitment and encourages osteoblast function). Combined use with alendronate has not been studied.
Adequate elemental calcium and vitamin D are needed. Calcium supplements should be taken at least half an hour after taking alendronate. Effervescent calcium (resulting in a solution) may be absorbed more rapidly and help avoid problems.

Beverages:

Any liquid other than water will decrease the amount of alendronate that gets into your body to help you. It is critical that this medicine only be taken with 6 to 8 ounces of water.

Alcohol:

Alcohol (especially in high doses) may act as a bone-forming cell (osteoblast) poison, and excessive use is a risk factor for osteoporosis. Alcohol may also irritate the stomach lining.

Tobacco smoking:

Smoking is a risk factor for osteoporosis. Stop smoking.

Heavy exercise or exertion:

If your bone density is low, heavy aerobic exercise may not be a good idea. Discuss this with your doctor. In general, weight- bearing exercise stimulates receptors (mechanoreceptors) to release factors that result in increased bone strength.

Discontinuation:

Talk with your doctor before stopping this medicine.