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Fosamax Side Effects


Fosamax is supposed to prevent age-related bone damage. Instead, people who took the drug may suffer from a wide range of side effects, including femur fractures, jaw problems and esophageal ulcers.

For many people, one of the many worries that come with getting older is the risk of developing osteoporosis. This debilitating disease makes bones so brittle they easily break.

When Fosamax was introduced in 1995, it was promoted as the solution to osteoporosis and other bone-damaging diseases. Instead, studies show that Fosamax (alendronate) causes a slew of side effects that may be more problematic than osteoporosis itself. The U.S. Food and Drug Administration (FDA) documented several of the drug’s side effects and subsequently distributed numerous warnings.

Fosamax belongs to the bisphosphonate drug family, which is known to cause many of the drug’s side effects. They range from mild to severe.

According to the drug’s manufacturer, Merck, the most common side effects include gastrointestinal issues, such as nausea, diarrhea, constipation and cramping. It can also cause skin rashes and eye problems.

Severe Side Effects

According to Merck, a defendant in litigation because of Fosamax, the more severe side effects include broken bones, jawbone deterioration, esophagus problems, low blood calcium, and extreme bone and joint pain.

Femur Fractures

For those taking Fosamax, perhaps the most frustrating side effect is the drug’s propensity to cause fractures of what is one of the strongest bones in the body – the femur. These low-energy fractures, also called stress fractures, often happen when patients least expect it. Some patients reported breaking bones while they were doing normal, everyday tasks such as walking or sitting. Merck said the fractures usually come after weeks or months of groin or hip pain. Researchers are still trying to determine why Fosamax is linked to bone breaks, especially in patients taking the drug for five years or longer. Many scientists theorize the drug shuts down the body’s bone-renewing process and creates more brittle bones.

Dead Jaw Syndrome (Osteonecrosis)

Another alarming side effect of Fosamax is jaw osteonecrosis, also called Dead Jaw Syndrome. This happens when the blood flow to the jawbone, or mandible, is cut off and causes bone death. Usually onset following minor mouth trauma such as dental work, jaw necrosis (cell death) causes an antibiotic-resistant infection and swelling. The infection eventually takes over the tissue and causes bone to die and collapse.

Esophagus Problems

Some Fosamax patients develop irritation, inflammation and bleeding ulcers in the esophagus, which is the tube that connects the mouth to the stomach. In addition, recent studies point to these problems leading to esophageal cancer. Those who have pre-existing known upper gastrointestinal problems, such as Barrett’s esophagus and dysphagia, should not take Fosamax. In some patients, Fosamax leads to esophageal erosion with bleeding and esophageal perforation. Because of these potentially dangerous side effects, Merck recommends that patients sit upright or stand for a full 30 minutes after taking the drug and take it with a full glass of water.

Low Blood Calcium

Also called hypocalcemia, low blood calcium levels can lead to hand and feet spasms, muscle cramps and abdominal cramps. Since bisphosphonates hinder the natural breakdown of bone, less calcium is deposited back into the blood stream. As the tissues and cells get robbed of calcium, patients can suffer from soft bones, nausea, fatigue and muscle weakness. This can also lead to spasmodic movements and seizures.

Musculoskeletal Pain

The FDA has also found that Fosamax patients can develop severe bone, muscle and joint pains within days of starting the drug. For some people, this pain stops almost immediately after discontinuing it. For others, it is ongoing. Even though it is well documented that Fosamax causes pain, some physicians are known to ignore this side effect, instead prescribing painkillers. The FDA has alerted medical professionals about this problem to ensure Fosamax-related pain won’t be overlooked.