Alendronate (Fosamax) Treatment for Osteoporosis
Alendronate (Fosamax) is recommended at a dose of 70 mg once weekly (preferred) or 10 mg daily for the treatment of osteoporosis in postmenopausal women and men, with strong evidence supporting its efficacy in reducing fracture risk. 1, 2
Indications and Patient Populations
Alendronate is FDA-approved for:
- Treatment of osteoporosis in postmenopausal women 2
- Prevention of osteoporosis in postmenopausal women 2
- Treatment to increase bone mass in men with osteoporosis 2
- Treatment of glucocorticoid-induced osteoporosis in men and women receiving glucocorticoids equivalent to ≥7.5 mg prednisone daily 2, 3
Dosage Recommendations
For Treatment of Osteoporosis:
For Prevention of Osteoporosis:
- 35 mg once weekly or 5 mg daily 1
Efficacy
Alendronate demonstrates significant efficacy in:
- Reducing vertebral fractures by 47-56% 1, 5
- Reducing hip fractures by approximately 50% 1, 5
- Reducing all clinical fractures by approximately 30% 1, 6
The American College of Physicians strongly recommends alendronate as a first-line therapy for osteoporosis treatment with high-quality evidence supporting its use 7, 1.
Administration Instructions
For optimal absorption and to minimize adverse effects:
- Take on an empty stomach after an overnight fast 8
- Take with a full glass of plain water (6-8 oz) 1
- Remain upright (sitting or standing) for at least 30 minutes after taking 1, 8
- Wait at least 30 minutes before consuming food, beverages, or other medications 1, 4
- For weekly dosing, take on the same day each week 1
Duration of Treatment
- The optimal duration of therapy is typically 5 years 7, 1
- Patients at low risk for fracture should be considered for drug discontinuation after 3-5 years 2
- After the initial 5-year treatment period, continuation should be reassessed based on individual fracture risk 1
Monitoring
- Routine bone mineral density (BMD) monitoring is not recommended during the initial 5-year treatment period 7, 1
- The American College of Physicians specifically recommends against bone density monitoring during the 5-year pharmacologic treatment period 7
Supplementation
Patients should receive adequate supplementation alongside alendronate:
Adverse Effects
Common adverse effects:
Rare but serious adverse effects:
Contraindications
Alendronate is contraindicated in patients with:
- Esophageal abnormalities that delay esophageal emptying 1
- Inability to stand/sit upright for at least 30 minutes 1
- Hypocalcemia 1
- Hypersensitivity to any component of the product 1
Special Populations
Men with Osteoporosis
- Alendronate 10 mg daily or 70 mg weekly is effective for increasing bone mass 2, 6
- The American College of Physicians recommends bisphosphonates for men with clinically recognized osteoporosis, though this is a weak recommendation with low-quality evidence 7
Glucocorticoid-Induced Osteoporosis
- Alendronate has demonstrated efficacy in preventing and treating glucocorticoid-induced bone loss 3
- Recommended for patients receiving glucocorticoids equivalent to ≥7.5 mg prednisone daily 2, 3
Clinical Pearls and Pitfalls
- Adherence is crucial: Poor adherence is associated with side effects, inconvenience of administration, and absence of symptoms 7
- Proper administration: Failure to follow administration instructions increases the risk of esophageal adverse events 1, 8
- Weekly dosing advantage: Once-weekly dosing provides equivalent efficacy to daily dosing with improved convenience and potentially better adherence 4
- Treatment duration: While 5 years is typical, the optimal duration has not been definitively determined and should be reassessed based on individual fracture risk 1, 2