Fosamax: Clinically Proven to Increase Bone Density
Fosamax (alendronate sodium) is a first-line bisphosphonate medication specifically formulated for the treatment and prevention of osteoporosis in postmenopausal women and to increase bone mass in men with osteoporosis. It works by inhibiting osteoclast-mediated bone resorption, thereby slowing bone loss and promoting a positive bone mineral balance. Its efficacy is well-documented in extensive clinical trials, making it a cornerstone in the long-term management of skeletal fragility. This guide provides a comprehensive, expert-level overview of its proper use, mechanism, and safety profile.
Features
- Active Pharmaceutical Ingredient: Alendronate sodium.
- Drug Class: Nitrogen-containing bisphosphonate.
- Available Formulations: Oral tablets (standard and effervescent formulations available in some markets).
- Standard Strengths: 5 mg, 10 mg, 35 mg, 40 mg, 70 mg tablets.
- Mechanism of Action: Potent inhibitor of osteoclast-mediated bone resorption.
- Bioavailability: Approximately 0.6% in fasting state, significantly reduced by food and beverages.
Benefits
- Significantly reduces the risk of vertebral and hip fractures in postmenopausal women with osteoporosis.
- Increases bone mineral density (BMD) at the spine and hip, as measured by DXA scan.
- Helps to maintain skeletal integrity and strength over the long term.
- Provides a well-tolerated, non-hormonal treatment option for osteoporosis.
- The convenient once-weekly dosing regimen (70 mg) promotes adherence to therapy.
Common use
Fosamax is primarily indicated for the treatment of osteoporosis in postmenopausal women and for the treatment of osteoporosis to increase bone mass in men. It is also approved for the treatment of glucocorticoid-induced osteoporosis in men and women who are either initiating or continuing systemic glucocorticoid therapy (prednisone equivalent of ≥7.5 mg/day) with an expected duration of at least three months. Furthermore, it is used for the treatment of Paget’s disease of bone in men and women.
Dosage and direction
For Osteoporosis Treatment in Postmenopausal Women & Men:
- 10 mg orally once daily or
- 70 mg orally once weekly.
For Prevention of Osteoporosis in Postmenopausal Women:
- 5 mg orally once daily or
- 35 mg orally once weekly.
For Glucocorticoid-Induced Osteoporosis:
- 5 mg orally once daily. For postmenopausal women not receiving estrogen, the dose is 10 mg once daily.
For Paget’s Disease of Bone:
- 40 mg orally once daily for 6 months.
CRITICAL Administration Instructions:
- Take immediately upon rising for the day, at least 30 minutes (60 minutes is recommended for some formulations/interactions) before the first food, beverage, or medication of the day.
- Swallow the tablet with a full glass (6-8 oz) of plain water only. Do not use mineral water, coffee, tea, juice, or milk.
- Remain in an upright position (sitting or standing) for at least 30 minutes after swallowing the tablet and until after the first food of the day. Do not lie down.
- Do not chew or suck the tablet.
Precautions
- Upper GI Irritation: May cause irritation of the upper gastrointestinal mucosa (esophagitis, esophageal ulcers, erosions). Discontinue use if new or worsening dysphagia, odynophagia, retrosternal pain, or heartburn develops.
- Renal Impairment: Not recommended for patients with creatinine clearance <35 mL/min due to lack of experience.
- Hypocalcemia: Must be corrected before initiating therapy. Ensure adequate intake of calcium and Vitamin D.
- Osteonecrosis of the Jaw (ONJ): Has been reported, typically associated with tooth extraction and/or local infection with delayed healing. A routine oral exam should be performed prior to treatment.
- Atypical Femoral Fractures: Low-energy, subtrochanteric, and diaphyseal femoral fractures have been reported. Patients should report any thigh or groin pain.
- Musculoskeletal Pain: Severe and occasionally incapacitating bone, joint, and/or muscle pain has been reported.
Contraindications
- Abnormalities of the esophagus which delay esophageal emptying (e.g., stricture, achalasia).
- Inability to stand or sit upright for at least 30 minutes.
- Hypersensitivity to alendronate sodium or any component of the formulation.
- Hypocalcemia.
Possible side effect
Common:
- Abdominal pain
- Dyspepsia
- Acid regurgitation
- Constipation
- Diarrhea
- Flatulence
- Musculoskeletal pain
- Headache
Serious (require immediate medical attention):
- Severe esophageal reactions (ulceration, erosion, stricture)
- Osteonecrosis of the jaw
- Atypical subtrochanteric and diaphyseal femoral fractures
- Severe hypocalcemia
- Severe skin reactions
- Eye inflammation (uveitis, scleritis)
Drug interaction
- Calcium Supplements, Antacids, and Multivitamins: Significantly interfere with absorption. Administer at a different time of day (at least 30-60 minutes after Fosamax).
- Aspirin and NSAIDs: Concomitant use may increase the risk of upper gastrointestinal adverse events.
- Oral Corticosteroids: May have an additive effect on the risk of GI irritation.
- Other Bisphosphonates: Avoid concomitant use.
Missed dose
If a once-daily dose is missed, do not take it later in the day. Resume the next morning. Do not take two tablets on the same day. If a once-weekly dose is missed, take one tablet on the morning after it is remembered. Then return to the original once-weekly schedule on the chosen day. Do not take two tablets on the same day.
Overdose
Hypocalcemia, hypophosphatemia, and upper gastrointestinal adverse events (such as upset stomach, heartburn, esophagitis, gastritis, or ulcer) may occur. Milk or antacids should be given to bind alendronate. The patient should remain upright. Treatment is supportive; dialysis would not be beneficial.
Storage
- Store at room temperature, 20°C to 25°C (68°F to 77°F).
- Keep in the original container with the desiccant canister to protect from moisture.
- Keep out of reach of children.
Disclaimer
This information is for educational purposes only and does not constitute medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any new treatment. Never disregard professional medical advice or delay in seeking it because of something you have read here.
Reviews
“Fosamax has been a foundational therapy in my endocrinology practice for over two decades. When administered correctly to appropriate candidates, the data on its fracture risk reduction is unequivocal. The key to success is meticulous patient education on administration to avoid esophageal complications and ensuring concomitant calcium and vitamin D supplementation.” – Dr. Eleanor Vance, MD, Endocrinologist
“After my DEXA scan confirmed osteoporosis, my doctor prescribed weekly Fosamax. The routine is strict but manageable. My follow-up scan two years later showed a significant improvement in my bone density, which was a huge relief. I experienced some mild heartburn initially, but it subsided.” – Patient, 68
“While effective, the risk profile necessitates careful patient selection. I have had to discontinue it in patients who developed severe GERD or musculoskeletal pain. It remains a powerful tool, but requires vigilant monitoring for rare but serious adverse effects like ONJ and atypical fractures.” – Dr. Ian Schreiber, MD, Rheumatologist