I was prescribed Fosamax (alendronate). What is that? What are the contraindications to taking it, and are there any side effects? I've heard that Fosamax can be very tough on the stomach. Is that true?
Fosamax (alendronate) is one of the bisphosphonates, a group of drugs used to treat or prevent osteoporosis as well as to prevent bone loss in early postmenopausal women. Fosamax does this by decreasing bone turnover. Fosamax and the three other FDA-approved bisphosphonates for treating or preventing osteoporosis—Actonel (risedronate), Boniva® (ibandronate), and Reclast® (zoledronic acid)—don't actually build bone, but they are very effective in preventing further breakdown of bone. By slowing bone turnover, bone mineral density increases. In fact, bisphosphonates can decrease spinal fracture risk in as little as 1 year of treatment. A fifth bisphosphonate, Didronel® (etidronate), also affects bone turnover and is FDA-approved for the treatment of Paget's disease. Questions 57 to 60 discuss Actonel, Boniva, Reclast, and Didronel.
Fosamax is FDA-approved for prescription daily or once a week in different doses for the purposes of preventing or treating osteoporosis in postmenopausal women, treating to increase bone mass in men with osteoporosis, or treating glucocorticoid-induced osteoporosis (GIO) in men or women with low BMD who are receiving daily doses of glucocorticoids > 7.5 mg. The dosage of Fosamax for GIO is one 5-mg tablet by mouth per day for men and women or 10 mg per day for postmenopausal women who are not taking estrogen. The BMD in individuals with GIO significantly increases after about 1 year of treatment using Fosamax. Either the 5-mg per day dose or one 35-mg tablet by mouth once a week is used to treat postmenopausal women with osteopenia, because the goal of osteopenia treatment is osteoporosis prevention. For the treatment of osteoporosis in postmenopausal women or to increase bone mass in men with osteoporosis, the dosage is one 10-mg tablet per day or one 70-mg tablet once a week. A month's supply of tablets, whether taken daily or weekly, costs about $85 to $90 without insurance coverage or co-pays.
Results of a 6-year study showed that women taking Fosamax and women taking EPT (estrogen-progestin therapy) both had increases in BMD. Fosamax and EPT were discontinued after 4 years and once again, BMD decreased in all of the postmenopausal women. However, those who had taken Fosamax had less bone loss after 2 years than those who took EPT.
Yes, it's true that Fosamax can be tough on your stomach, and if you already have stomach ulcers or reflux disease, it should be used with extreme caution. Stomach upset and the risk for ulcers is further increased if you are taking nonsteroidal anti-inflammatory medications (NSAIDs) such as ibuprofen (e.g., Motrin, Nuprin), naproxen (e.g., Aleve), or aspirin while you are on Fosamax. You can minimize the negative effects such as heartburn and stomach upset by following strict guidelines. Whether you take Fosamax daily or weekly, you must take it using these same guidelines:
• If you are on the weekly version of Fosamax, pick a day and stick with it. Most people pick Sunday unless they are too tempted to go back to sleep.
Fosamax tablets come with tiny stickers to put on your calendar as reminders to take it. If you happen to forget to take it on the day it is due (e.g., Sunday), then take it the very next day (e.g., Monday).
• Take it on an empty stomach. Food interferes with its absorption. So does any liquid except PLAIN water.
• You must swallow the tablet whole. Do not chew or suck on it.
• When you are up for the day (meaning that you are not going to lie down after taking it), take the tablet with a 6- to 8-ounce glass of PLAIN water, not seltzer water, not fruit-flavored water, and not any other beverage made with water. Never take Fosamax before retiring for the night. Only take it with plain water.
• Take nothing else for at least 30 minutes. Do not take calcium, vitamin D, minerals, or antacids within 2 hours of taking Fosamax.
• Do not lie down or bend at the waist. Don't go back to bed. Bending at the waist or lying down can make the medication reflux into your esophagus and increase the chance of heartburn.
• You may eat and take other medications after 30 minutes, except milk and those items previously mentioned.
Bisphosphonates may cause inflammation of the stomach or esophagus, nausea, vomiting, constipation, diarrhea, flatulence, ulcer, swelling, or abdominal, muscle, back, or joint pain. Although very rare, osteonecrosis of the jaw (ONJ; deterioration of bone tissue) following dental surgery has been reported in patients taking long-term intravenous bisphosphonate therapy used for treating cancer and reducing bone pain and cancer-related high levels of blood calcium. Most reports were in patients taking intravenous (IV) bisphosphonate therapy. Extremely rare cases have been reported in those taking the medications by mouth.
ONJ happens when bone tissue in the jaw is exposed for 3 months or more and nonhealing lesions are identified. Patients at risk are people with cancer who are taking high-dose IV bisphosphonates, have poor dental health, have abnormalities in the mouth bones, have injuries to their gums, or are taking medications that interfere with healing. ONJ is very rare, affecting 2% to 10% of patients taking high-dose IV bisphosphonates for bone-related cancers. Occurrence rates among healthy people taking bisphosphonates for osteoporosis prevention or treatment are estimated at less than 1% (0.001% to 0.002%). ONJ is most likely to happen after an invasive dental procedure. It is important to inform your dentist if you are taking or have previously taken bisphosphonates and to maintain good dental hygiene (brushing regularly, having regular dental check-ups and cleanings, avoiding sticky candies, and using fluoride toothpaste), which can further reduce the small risk for ONJ.
Fosamax is strictly contraindicated if you have an allergy to bisphosphonates or advanced kidney disease. Caution should be used when Fosamax is taken by anyone with existing stomach or intestinal disease. Table 8 summarizes the contraindications and considerations for taking Fosamax. While the majority of Fosamax's side effects are related to heartburn, you should always immediately report chest pain, difficulty swallowing, or severe midline heartburn.
The FDA also approved Fosamax Plus D™, a weekly tablet that contains the same 70 mg of alendronate found in the weekly Fosamax tablet, but also has added vitamin D. The 2800 IU of vitamin D in Fosamax Plus D is the typical weekly amount recommended for people aged 51 to 70. If you are over the age of 70, you will
Table 8 Fosamax (alendronate)
need to make sure that you still get an additional 200 IU per day of vitamin D. Table 8 reviews the indications and considerations for using Fosamax.
The long-term safety of Fosamax has been established in those taking it for 10 years or more. Several studies have shown that bone density does increase, and safety is maintained in patients who take Fosamax for >10 years. Additionally, some bone protection persists even after Fosamax is stopped in those who have taken it for 5 years continuously. Very long-term use of Fosamax may be associated with oversuppression of bone turnover. This causes the quality of the bone to suffer because there is not the usual turnover of older bone tissue due to the inhibition of osteoclast activity, rendering the bone more fragile. One study found that longer use of Fosamax was associated with higher risk for low-trauma fracture of the thigh bone (femur). More research is needed to identify whether this increased risk for fracture is only related to long-term use of alendronate or to all bisphosphonates.
The long-term effects of Fosamax could be a concern even after it is discontinued. The half-life of Fosamax can exceed 10 years. This means that it can take a very long time for the body to eliminate all of the Fosamax that has been absorbed. Effects on bone are likely to be positive, but it is not clear how a future pregnancy would be affected by the continued effects of Fosamax or other bisphosphonates. Fosamax is not FDA-approved for use in premenopausal women except those with GIO. If a premenopausal woman had a fragility fracture (see Question 74), a specialist may consider treatment with a bisphosphonate. This would only be considered if other potential causes for the fracture were ruled out and if she were on a very reliable method of birth control or unable to conceive.