What is the average time to see bone growth with Fosamax (alendronate)?

From the Guidelines

Bone growth with Fosamax (alendronate) typically becomes measurable after 3-6 months of consistent treatment, though significant improvements in bone mineral density (BMD) are usually observed after 12 months of therapy. Patients taking the standard dose of 70 mg once weekly (or 10 mg daily) can expect BMD increases of approximately 3-5% at the spine and 1-3% at the hip after the first year of treatment 1. These improvements continue more gradually with ongoing therapy, with maximum effects often seen after 3-5 years. For optimal results, Fosamax should be taken on an empty stomach with a full glass of water at least 30 minutes before the first food or drink of the day, and patients should remain upright for at least 30 minutes after taking it. Fosamax works by inhibiting osteoclasts (bone-resorbing cells), which slows bone breakdown and allows osteoblasts (bone-building cells) to work more effectively, gradually improving bone density and strength. Calcium and vitamin D supplementation is typically recommended alongside Fosamax to provide the necessary building blocks for new bone formation.

Key Considerations

• The American College of Physicians recommends offering pharmacologic treatment with alendronate to reduce the risk for hip and vertebral fractures in women with known osteoporosis 1.
• Treatment with alendronate has been shown to reduce the risk of vertebral fracture in men with clinically recognized osteoporosis 1.
• The optimal duration of treatment with alendronate is not well established, but the American College of Physicians recommends treating osteoporotic women with pharmacologic therapy for 5 years 1.
• Bone density monitoring during the 5-year pharmacologic treatment period is not recommended for osteoporosis in women 1.

Additional Information

The management of osteoporosis in survivors of adult cancers with nonmetastatic disease also involves the use of antiresorptive treatments, such as denosumab and bisphosphonates, including alendronate 1. The European Calcified Tissue Society suggests the use of a bisphosphonate to reduce the risk of vertebral fractures upon stopping denosumab 1. Overall, the use of Fosamax (alendronate) is an effective treatment for improving bone density and reducing the risk of fractures in patients with osteoporosis.

From the FDA Drug Label

In osteoporosis treatment studies alendronate sodium 10 mg/day decreased the markers of bone formation, osteocalcin and bone specific alkaline phosphatase by approximately 50%, and total serum alkaline phosphatase by approximately 25 to 30% to reach a plateau after 6 to 12 months The decrease in the rate of bone resorption indicated by these markers was evident as early as one month and at three to six months reached a plateau that was maintained for the entire duration of treatment with alendronate sodium The mean increases from baseline in lumbar spine BMD at one year were 5.1% (4.8,5. 4%; 95% CI) in the 70-mg once-weekly group and 5.4% (5.0,5. 8%; 95% CI) in the 10-mg daily group

The average length of time to see bone growth with Fosamax (alendronate) is 3 to 6 months for the decrease in bone resorption to reach a plateau, and 6 to 12 months for bone formation markers to reach a plateau, with significant increases in bone mass at 1 year 2 2.

• Key points:
  • Decrease in bone resorption markers evident as early as 1 month
  • Plateau in bone resorption markers reached at 3 to 6 months
  • Plateau in bone formation markers reached at 6 to 12 months
  • Significant increases in bone mass at 1 year

From the Research

Average Time to See Bone Growth with Fosamax (Alendronate)

• The average time to see bone growth with Fosamax (alendronate) can vary depending on several factors, including the dosage, frequency of administration, and individual patient response 3, 4, 5, 6, 7.
• Studies have shown that alendronate can increase bone mineral density (BMD) in as little as 12 months, with significant improvements observed in the lumbar spine and total hip 4, 5, 6.
• One study found that patients treated with alendronate 70 mg once weekly for 12 months had a mean increase in lumbar spine BMD of 5.2% and a mean increase in total hip BMD of 2.9% 4.
• Another study found that patients treated with alendronate 10 mg daily for 2 years had a mean increase in lumbar spine BMD of 8.36% and a mean increase in femoral neck BMD of 8.17% 5.
• A study on Chinese post-menopausal women at risk of osteoporosis found that bi-weekly alendronate (70 mg every 2 weeks) plus daily alfacalcidol (0.5 μg) for 12 months significantly increased lumbar spine and total hip BMD compared to alfacalcidol alone 6.
• A clinical trial on people with spinal cord injury and low bone mineral density found that alendronate 70 mg once weekly for 12 months after teriparatide therapy prevented bone loss and increased bone mass at the spine, hip, and some sites of the knee 7.

Factors Influencing Bone Growth with Fosamax

• Dosage and frequency of administration: Studies have used various dosages and administration frequencies, including 70 mg once weekly 3, 4, 10 mg daily 5, and 70 mg every 2 weeks 6.
• Individual patient response: Patient response to alendronate can vary, with some studies reporting significant improvements in BMD and others reporting minimal changes 4, 5, 6, 7.
• Duration of treatment: The duration of treatment can also impact bone growth, with longer treatment periods generally resulting in greater improvements in BMD 5, 7.