Alendronate

Alendronate: Patient Information Guide for Australians

1. Basic Product Information

• International Non-Proprietary Name (INN): Alendronate Sodium
• Common Brand Names in Australia: Fosamax®, Alenat®, Adronat®, Alendros
• ATC Code: M05BA04
• Available Forms and Strengths: Tablets (mainly 70 mg once weekly, some 10 mg daily), effervescent tablets, and oral solutions
• Common Manufacturers: Merck Sharp & Dohme (Australia) Pty Ltd, Apotex, Sandoz, others
• Prescription Status: Schedule 4 (Prescription Only Medicine) in Australia

2. Mechanism of Action

For Patients: Alendronate belongs to a group of medicines called bisphosphonates. It helps slow down bone loss and strengthens bones, making them less likely to break. Alendronate does this by reducing the activity of the cells that break down bone.
For Healthcare Professionals: Alendronate is a nitrogen-containing bisphosphonate that inhibits osteoclast-mediated bone resorption by binding to hydroxyapatite in bone matrix. It specifically inhibits farnesyl pyrophosphate synthase in the mevalonate pathway, reducing osteoclast activity and promoting apoptosis of bone-resorbing cells.

3. Pharmacokinetics

• Absorption: Oral bioavailability is <2% in fasting conditions. Food and some beverages (especially calcium-rich drinks) can significantly reduce absorption.
• Distribution: Rapidly binds to bone tissue; not distributed widely in soft tissue.
• Metabolism: Not metabolised; excreted unchanged.
• Elimination: Excreted via the kidneys (urine); half-life in bone may exceed 10 years due to binding.
• Duration of Action: Effects on bone turnover last for weeks to months after a single dose.

4. Use in Everyday Life and Best Practices

• Alendronate is usually prescribed for osteoporosis, especially in postmenopausal women and older men, to reduce fracture risk.
• Common dosing:
  • 70 mg tablet taken once weekly (preferred)
  • Or 10 mg tablet taken daily (less common)
• Alendronate is taken as a tablet by mouth, ideally at the same time every week (for weekly dosing) to help establish a routine.
• Avoid lying down for at least 30 minutes after taking the medicine and until after your first food of the day.

5. Dosing: Morning vs Evening

• Best practice: Always take alendronate in the morning upon waking, before eating or drinking anything (other than a full glass of plain water). This improves absorption and reduces the risk of side effects.
• Evening use is strongly discouraged due to increased risk of stomach irritation and reduced absorption.
• Setting a weekly reminder (e.g. Sunday morning) may help with regularity.
• Use with caution in patients with difficulty remembering routines—consider family involvement or pill organisers.

6. Taking With Food or on an Empty Stomach

• Food, beverages (other than water), and supplements containing calcium or magnesium should be avoided for at least 30 minutes after taking alendronate as they can severely reduce absorption.
• Plain tap water (not mineral water) should be used to swallow the tablet.
• In the context of a typical Australian diet, pay attention to dairy products, calcium-fortified cereals, and coffee during breakfast—avoid them until after 30 minutes has passed post-dose.

7. Interaction Warnings

8. Indications for Alendronate

9. Dosing According to Clinical Indications

10. Safety Profile and Side Effects

11. Guidelines for Proper Use (Pharmacist/Clinic Advice)

• Take your dose first thing in the morning, with a full glass of plain water (not mineral/sparkling water).
• Swallow tablet whole—do not chew, suck, or crush.
• Remain upright (sitting or standing) for at least 30 minutes after taking alendronate and until after eating.
• Wait at least 30 minutes before taking any food, beverages, or other medicines.
• Do not take at bedtime or before rising for the day.
• If you miss a weekly dose, take it the next morning and resume your usual schedule; do not double dose.
• Routine dental check-ups are important. Inform your dentist you’re taking alendronate.
• Report persistent abdominal pain, swallowing difficulties, or new thigh/jaw pain to your doctor.
• Discuss with your pharmacist about pill organisers, reminders, and leaflet advice for medicines with complex administration instructions.

12. Alternative Treatment Options

• Risedronate: Another bisphosphonate, similar dosing, available on the PBS (Pharmaceutical Benefits Scheme).
• Ibandronate: Monthly tablet or intravenous forms; alternative for those intolerant to alendronate.
• Zoledronic acid: Once-yearly IV infusion; PBS reimbursement for certain patients, useful for those with adherence issues or GI intolerance.
• Denosumab (Prolia®): 6-monthly subcutaneous injection; PBS reimbursed for osteoporosis in some cases, generally well-tolerated.
• Teriparatide: Daily injection; reserved for severe osteoporosis under specialist supervision, eligible for PBS under strict criteria.
• Hormone replacement therapy (HRT) and Selective Estrogen Receptor Modulators (SERMs, e.g. raloxifene): Used for select patients, especially menopausal women.

Summary: Alendronate is often the first-line treatment because of its established safety, convenience, and cost-effectiveness. Alternatives exist for specific patient needs (e.g., intolerance, adherence challenges).

13. Legal, Registration, and Reimbursement Status in Australia

• Legal status: Schedule 4 (S4)—Prescription Only
• Regulation: Registered by the Therapeutic Goods Administration (TGA)
• PBS reimbursement: Alendronate (and many alternatives) are reimbursed under the Pharmaceutical Benefits Scheme (PBS) for approved indications such as osteoporosis
• For hospital and community pharmacy use: Available with a valid prescription from a registered medical practitioner, but not available for over-the-counter purchase

14. Latest Research & Clinical Guidance (2022–2025)

• The 2022–2023 RACGP and Osteoporosis Australia guidelines continue to recommend alendronate as a safe and effective first-line treatment for osteoporosis in both women and men, including those on long-term glucocorticoids.
• Long-term studies (up to 10 years) confirm efficacy in fracture prevention and support the use of “drug holidays” after 3–5 years in low-risk patients to minimise rare adverse effects like atypical femur fractures (Leder BZ, N Engl J Med 2024; Watts NB, Med J Aust 2023).
• Denosumab is considered an equal alternative for patients intolerant of bisphosphonates (Milinis K et al., MJA 2023), but abrupt discontinuation should be avoided due to rapid bone loss.
• Current focus is on shared decision-making, good communication about administration, and better patient adherence strategies.

15. Availability and Delivery in Australia

Shipping is available nationwide. Rural and remote delivery usually within 5–7 working days.

16. Frequently Asked Questions (FAQ)

1. Q: What should I do if I miss a dose of alendronate?
   A: Take it the following morning after you remember. Then return to your regular schedule. Do not take two tablets on the same day.
2. Q: Why must I remain upright after taking alendronate?
   A: Remaining upright (sitting or standing) for at least 30 minutes helps the tablet pass quickly into your stomach and reduces the risk of irritation or ulceration of the oesophagus (food pipe).
3. Q: Can I take alendronate with my morning coffee or juice?
   A: No. Take alendronate with plain tap water only. Avoid all other drinks (including coffee, tea, juice, or mineral water) for at least 30 minutes after your dose.
4. Q: Is alendronate safe for long-term use?
   A: Yes, when taken as prescribed for osteoporosis. Your doctor will review your bone health regularly to determine the best duration, including considering a “drug holiday” after several years if you are low risk.
5. Q: Will taking calcium and vitamin D with alendronate help?
   A: Yes, adequate calcium and vitamin D are important for bone health, but these should be taken at a different time of day (not within 30–60 minutes of alendronate).