Actonel is a medication prescribed to treat osteoporosis, which is a condition in which bones lose density and become brittle, which in turn increases the likelihood of a break or a fracture. It’s more common in older women but can occur in anyone. Many rely on Actonel to prevent their bones from breaking easily in the event of a fall or other accident. However, taking Actonel could result in severe side effects such as esophageal erosion, low blood calcium, osteonecrosis of the jaw (ONJ), and atypical thigh bone fractures.

Lawsuits have been filed as a result due to the manufacturer’s failure to adequately warn of the potentially severe negative effects that could occur.

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What Is Actonel?

Actonel is a brand name of the medication risedronate. This type of medication is a bisphosphonate, which means that it’s designed to prevent or slow bone loss. Actonel and other bisphosphonates encourage the strengthening of bones while simultaneously discouraging the process of bone loss. Actonel is used to treat conditions such as osteoporosis.

Who Manufactures Actonel?

Actonel was approved in 1998 and was initially manufactured by consumer products giant, Procter & Gamble but is now manufactured by Allergan. Both companies have faced numerous Actonel lawsuits filed by people who experienced bone fractures, cancer, or other complications after using Actonel.

How Does Actonel Work?

Actonel works by enabling osteoblasts, which are the specialized cells that build bones, to work better to strengthen bone mass throughout the body. At the same time, Actonel inhibits osteoclasts, which are cells that break down bone tissue and reabsorb minerals, including calcium, from the bones. 

What Does Actonel Treat?

Actonel is typically used to treat osteoporosis and Paget’s disease. The medication can also sometimes be prescribed to treat high calcium levels in people who experience that condition as a symptom of cancer.

What Is Osteoporosis?

Osteoporosis is a disease that weakens the bones and causes them to become brittle. People who suffer from osteoporosis are more likely to experience fractures from falling, or even bending over or coughing, than other people. Osteoporosis is most common in postmenopausal women but can occur in anyone.

What Are the Symptoms of Osteoporosis?

In many cases, people with osteoporosis are unaware that they have the disease until they experience a fracture in the later stages of the disease’s progression. This is because the earlier stages often have no symptoms.

In the later stages, symptoms of osteoporosis can include the following:

  • Stooped posture
  • A loss of height
  • Bones breaking of fracturing more easily
  • Back pain

What Causes Osteoporosis?

Osteoporosis is caused by a slowing down of the bone-rebuilding process. Your bones are constantly rebuilding themselves; old bone material gets broken down and then the new bone is produced to replace it. In younger people, bone mass increases because the process of producing new bone is faster than the process that breaks it down. Bone production normally slows down when people reach their 20s and, typically, they reach their top bone mass in their 30s.

This means that after the 30s, the process of breaking down bone material starts to work faster than the production of new bone. Osteoporosis occurs when enough bone mass is lost without being replaced and bones are at greater risk of fracture.

Who Is at Risk of Developing Osteoporosis?

The following factors may impact whether you’re at greater risk of osteoporosis:

  • Gender (women)
  • Age (older age)
  • Race (Asian or Caucasian descent)
  • Genetics (family history of osteoporosis)
  • Body size (smaller body frame)
  • Your diet (low calcium intake)
  • Lower levels of estrogen
  • Thyroid issues
  • Gastrointestinal surgery
  • Eating disorders
  • Tobacco use
  • Sedentary lifestyle
  • Alcohol consumption (more than 2 drinks per day on a regular basis)
  • Celiac disease
  • Inflammatory bowel disease
  • Cancer
  • Rheumatoid arthritis
  • Multiple myeloma
  • Kidney disease
  • Liver disease
  • Long-term use of steroids
  • Cancer medication
  • Seizure medication
  • Gastric reflux medication
  • Transplant rejection medication

Why Are Postmenopausal Women More Likely to Get Osteoporosis?

Postmenopausal women may be more likely to develop osteoporosis. This is because, after menopause, the estrogen levels in the body are reduced. This loss of estrogen may result in bone loss and, if you were starting with a lower bone mass, then osteoporosis may occur.

What Is Paget’s Disease?

Paget’s disease is a condition in which the body doesn’t properly recycle bone. This means that the process of replacing the older bone tissue with new bone cells may not work the right way and bones may become misshapen and fragile. This disease most often impacts the skull, spine, pelvis, and legs.

What Are the Symptoms of Paget’s Disease?

The symptoms of Paget’s disease may vary depending on where in the body it’s located.

The symptoms may include:

  • Skull:
    • Hearing loss
    • Headaches
  • Spine:
    • Pain in an arm or leg
    • Tingling in an arm or leg
    • Numbness in an arm or leg
  • Pelvis:
    • Hip pain
  • Legs:
    • Osteoarthritis in the knees
    • Osteoarthritis in the hips
    • Bowleggedness

What Causes Paget’s Disease?

It’s currently unknown exactly what causes Paget’s disease. Scientists who study the disease believe that it’s a combination of genetic and environmental factors are the cause and several genes have been linked to the development of the disease. There is also a controversial theory that Paget’s disease is caused by bone cell viral infection.

Who Is at Risk of Developing Paget’s Disease?

The factors that may increase your risk of developing Paget’s disease include:

  • Age (over the age of 50)
  • Gender (men)
  • Genetics (family history)
  • National origin (Scotland, England, Greece, Central Europe, and places settled by people from those locations)

What Are the Side Effects of Actonel?

Actonel is a member of the bisphosphonate group of medications and may cause the same side effects as other medications in that group. While some of these side effects are mild to moderate and will go away with time, others are more severe or serious and may be life-threatening. Some of the most severe Actonel side effects are bone fractures from continued use, esophageal erosion, bladder cancer, and osteonecrosis of the jaw (ONJ).

As a result of these Actonel side effects, the U.S. Food and Drug Administration (FDA) reviewed and issued a warning regarding long-term use of Actonel. The FDA has warned both doctors and patients that the medication may not be safe if used longer than five years.

What Are the Common Side Effects of Actonel?

Actonel side effects may include serious health issues such as problems with the esophagus, low calcium in the blood, jawbone necrosis, and unusual fractures of the femur (thigh bone). These effects may range from mild to severe.

The most common side effects of Actonel may include:

  • Heartburn
  • Indigestion
  • Diarrhea
  • Stomach pain
  • Back pain
  • Joint pain
  • Muscle pain

To help reduce the chance of esophageal irritation, patients are instructed to take Actonel first thing in the morning before anything else is consumed. The medication should be swallowed with a full glass of water and the patient is instructed to avoid laying down or eating for at least 30 minutes after the medication has been taken.

What Is Esophageal Erosion?

Esophageal erosion is wear and tear that occurs on the esophagus, which is the pipe that connects the mouth to the stomach. This type of damage is usually caused by acid reflux, GERD, or another type of gastrointestinal or digestive issue that results in stomach acid entering the esophagus, which doesn’t have the same protection against acid as the stomach does. Actonel can irritate the esophagus and, over time, also result in esophageal erosion.

What Are the Symptoms of Esophageal Erosion?

The symptoms of esophageal erosion can include:

  • Irritation
  • Inflammation
  • Heartburn
  • Ulcers
  • Difficulty swallowing
  • Painful swallowing
  • Stricture
  • Pain
  • Bleeding
  • Tooth decay

How Does Actonel Cause Esophageal Erosion?

Actonel doesn’t directly cause esophageal erosion. Heartburn, however, does. Because heartburn is one of the possible side effects of taking Actonel, esophageal erosion could eventually result.

What Is Heartburn?

Heartburn occurs when you feel a burning sensation in your chest as a result of acid reflux. Acid from the stomach backs up into the esophagus and while the stomach lining protects the stomach from getting damaged by the strength of the acid, the esophagus doesn’t, which leaves it vulnerable. Heartburn can be painful and, over time, repeated exposure to stomach acid can cause damage and scarring to the esophagus.

The symptoms of heartburn include:

  • A bitter taste in the mouth
  • An acidic taste in the mouth
  • Pain that worsens when:
    • Lying down
    • Bending over
  • A burning sensation in the chest occurring:
    • At night
    • After eating

What Is Low Blood Calcium?

Another potential side-effect of taking Actonel is lower blood calcium. Calcium is required by the body for a variety of tasks, ranging from moving your muscles to carrying messages to and from the brain and the nerves. In the blood, calcium is used to help move blood cells around your body.

Taking Actonel may lower the amount of calcium that gets absorbed into the bloodstream, which may cause additional adverse side effects, such as:

  • Nausea
  • Fatigue
  • Spasms
  • Twitching
  • Cramps
  • Tingling
  • Numbness

What Is Osteonecrosis of the Jaw?

Actonel has been shown to increase the risk of osteonecrosis of the jaw (ONJ). ONJ is a potentially severe condition in which the jawbone either begins to decay or has become decayed and may be referred to as dead jaw syndrome.

What Are the Symptoms of Osteonecrosis of the Jaw?

Symptoms of Actonel osteonecrosis of the jaw may include:

  • Pain
  • Inflammation of the soft tissue
  • Secondary infection
  • Drainage

How Does Actonel Cause Osteonecrosis of the Jaw?

ONJ often occurs after dental work has been performed which may have resulted in small cuts or wounds in the mouth. Afterward, the area may be slow to heal or may not heal properly, causing blood flow to the jawbone to be restricted and resulting in the gradual death of the bone. Careful dental hygiene is essential when taking Actonel.

Patients may develop Actonel-related osteonecrosis of the jaw after as little as 12 months of taking Actonel or another bisphosphonate drug. The longer the drug is taken, the greater the risk of developing osteonecrosis of the jaw. The majority of Actonel osteonecrosis of the jaw cases occur in patients who received treatment for longer than 5 years.

Who Is at Risk of Developing Osteonecrosis of the Jaw?

The risk of Actonel osteonecrosis of the jaw is higher in patients who receive bisphosphonate as a treatment for cancer. Dosages of Actonel and other bisphosphonates may be as much as 10 times higher when used to treat cancer. Additionally, cancer patients often receive the drug intravenously as often as every month. Osteoporosis patients may only receive one IV dose per year.

What Are Atypical Thigh Bone Fractures?

Though Actonel is given to prevent bone fractures, it may contribute to unusual breakage of the femur, or thigh bone, from minor stress. These types of fractures have often occurred while patients were walking normally, under low-stress conditions. Fractures typically occur in the long section of the leg bone or in the area of the femur just below the hip joint. They are not the type of fractures commonly associated with osteoporosis but are a unique side effect of the drug.

How Does Actonel Cause Atypical Bone Fractures?

The bone fracture side effect risk may occur as part of the way Actonel and other bisphosphonates work. The primary effect of the medication is through slowing down the process of “bone remodeling” which repairs small cracks in the bone structure. Over time, the small breaks become numerous from everyday activity and cause the bone structure to become brittle.

How Have Studies Linked Actonel to Atypical Bone Fractures?

In March 2010, the U.S. Food and Drug Administration (FDA) announced an investigation of bisphosphonate drugs like Actonel after research conducted by the American Society of Bone and Mineral Research showed that rare but serious femur fractures are associated with long-term use of bisphosphonates.

The 2010 study published in the Journal of Bone and Mineral Research showed that 94 percent of femur fractures examined were caused by bisphosphonate medications, most of whom had taken the medication for five or more years. The research indicated that a warning sign of femur fracture related to Actonel or bisphosphonate use is persistent pain in the thigh or groin.

How Common Are Atypical Bone Fractures With Actonel?

Research has indicated that these types of bone fractures are usually rare. However, a study assessing the risk of atypical femur fractures showed an increased rate based on the duration of treatment from Actonel. The rates increased from 2 to 78 out of 100,000 per year between two and six years of treatment using Actonel.

What Actonel Lawsuits Are There?

Healthcare giant Procter & Gamble has faced a number of Actonel lawsuits filed by people who may have experienced injury after taking the medication. These injuries included osteonecrosis of the jaw as well as atypical thigh bone fractures as a result of taking Actonel. Robert Chickis filed suit in 2004 in Pennsylvania, alleging that Procter & Gamble failed to warn of the risks of Actonel.

Actonel is now manufactured by Allergan, who may also be facing a number of lawsuits for drug injuries including esophageal cancer, osteonecrosis of the jaw, bone fractures, and other serious side effects. No group consolidations or settlements for Actonel lawsuits have been announced.

Notwithstanding claims relating to this product, the drug/medical device remains approved by the U.S. FDA.


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