Difference Between Actonel & Fosamax

Osteoporosis is caused by thinning bone tissue and degeneration over time. Actonel and Fosamax are both bisphosphonates, a class of drugs that prevent bone resorption and increase bone mineral density (BMD) in someone with osteoporosis. There are a few differences between Actonel and Fosamax.

Benefits

• Both drugs inhibit osteoclasts, the bone cells responsible for breaking down old bone tissue, resulting in faster growth of new bone and longer retention of older bone tissue.

FACT Study

• The FACT (Fosamax Actonel Comparison Trial) study, a12-month study conducted in 2004 and published in the Sept. 29, 2004, issue of the "Journal of Bone and Mineral Research," concluded that Fosamax showed a significant level of improvement in BMD over Actonel.

Expert Insight

• Neil Gonter, M.D., an internist and rheumatologist who acts as an expert for the website OsteoporosisConnection.com, points out that both medications reduce bone fractures, which is the goal of the medications.

Time Frame

• Outcomes of the FACT study suggest Fosamax appears to work more quickly than Actonel, but both drugs produced similar results when patients were tested two years later, according to Dr. Gonter.

Side Effects

• The most common side effects reported with Actonel include high blood pressure, bladder infections and diarrhea. The most common side effects of Fosamax include joint pain, swelling in the hands and jaw numbness. Both drugs can cause back pain, heartburn and a worsening of acid reflux, along with dizziness, gas and abdominal pains.