From the Guidelines
Risedronate (Actonel) and Alendronate (Fosamax) are both effective bisphosphonate medications for treating osteoporosis, but Alendronate is typically considered first-line due to its extensive evidence base and lower cost as a generic medication. Both medications have been evaluated in the treatment of low bone density or osteoporosis to prevent fractures in men and women, as outlined in the American College of Physicians guideline update 1. The guideline recommends offering pharmacologic treatment with alendronate, risedronate, zoledronic acid, or denosumab to reduce the risk for hip and vertebral fractures in women with known osteoporosis, with alendronate and risedronate being specifically mentioned for their reduction in nonvertebral fracture risk.
Some key differences between the two medications include:
- Alendronate is usually prescribed at 70mg once weekly or 10mg daily, while Risedronate is prescribed at 35mg once weekly or 150mg once monthly
- Risedronate may cause less esophageal irritation, making it preferable for patients with upper GI sensitivity
- Both medications have comparable efficacy in reducing vertebral fractures, with alendronate possibly showing slightly better hip fracture prevention
The choice between Alendronate and Risedronate often depends on patient-specific factors, such as:
- Cost considerations and insurance coverage
- Tolerance and potential for adverse effects, such as mild upper GI symptoms, atypical subtrochanteric fracture, and osteonecrosis of the jaw, which are associated with bisphosphonates in general 1
- Adherence potential, given the similar administration requirements for both medications, including taking on an empty stomach with a full glass of water and remaining upright for 30-60 minutes afterward.
From the Research
Comparison of Risedronate and Alendronate
- Risedronate and Alendronate are both bisphosphonates used in the treatment of osteoporosis, with the goal of increasing bone mineral density (BMD) and reducing the risk of fractures 2.
- A 24-month study comparing the effects of Alendronate 70 mg once weekly and Risedronate 35 mg once weekly on BMD in postmenopausal women with osteoporosis found that Alendronate produced significantly greater BMD gains at all measured sites, including the hip trochanter, lumbar spine, total hip, and femoral neck 2.
- The same study also found that Alendronate resulted in significantly larger decreases in bone turnover marker levels compared to Risedronate, indicating a greater reduction in bone resorption 2.
- In terms of tolerability, no significant differences were seen in the incidence of upper gastrointestinal (UGI) or other adverse events between the two treatments 2.
- A network meta-analysis comparing the efficacy of different bisphosphonates, including Alendronate and Risedronate, found that Zoledronic acid was the most effective in preventing vertebral fracture, nonvertebral fracture, and any fracture, while Alendronate or Zoledronic acid were the most effective in preventing hip fracture 3.
- Patient preference studies have shown that once-weekly Alendronate 70 mg is preferred over once-daily Alendronate 10 mg due to its convenience and potential for improved long-term compliance 4.
Efficacy and Safety
- Both Alendronate and Risedronate have been shown to be effective in increasing BMD and reducing the risk of fractures in postmenopausal women with osteoporosis 5, 2.
- Alendronate has been found to be generally well-tolerated, with most adverse events being transient and associated with the upper GI tract 5.
- Risedronate has also been shown to be well-tolerated, with a similar incidence of adverse events compared to Alendronate 2.