Ostolek (Alendronate Sodium Trihydrate)

Alendronate sodium works on the skeletal system to reduce bone loss and strengthen bone architecture.

• Osteoporosis: improves bone mineral density and reduces fracture risk in post‑menopausal women and men.
• Paget’s disease of bone: normalises abnormal bone remodeling and alleviates bone pain.
• Glucocorticoid‑induced osteoporosis: counteracts steroid‑related bone loss and helps maintain skeletal strength.

• Alendronate sodium trihydrate binds avidly to hydroxyapatite crystals on bone surfaces, especially at sites of active remodeling. When osteoclasts attach to the drug‑coated bone, it is internalised and inhibits farnesyl pyrophosphate synthase in the mevalonate pathway, disrupting prenylation of essential proteins and ultimately inducing osteoclast apoptosis, thereby reducing bone resorption.

Alendronate sodium may cause a range of adverse reactions, from mild gastrointestinal discomfort to rare but serious complications.

Common Side Effects

• Upper abdominal pain: mild discomfort after oral intake.
• Nausea: occasional feeling of queasiness.
• Dyspepsia: indigestion or heartburn.
• Esophageal irritation: soreness or burning in the throat.
• Musculoskeletal pain: aches in joints or muscles.
• Headache: mild to moderate head pain.

Serious or Rare Side Effects

• Osteonecrosis of the jaw: exposed bone in the mouth, often after dental procedures.
• Atypical femoral fracture: unusual breakage of the thigh bone with minimal trauma.
• Severe esophageal ulceration: deep sores that may cause bleeding.
• Acute phase reaction: fever, myalgia, and flu‑like symptoms after the first dose.
• Hypocalcaemia: low blood calcium levels, potentially causing muscle cramps or cardiac arrhythmia.

Before initiating therapy, evaluate renal function, calcium status, and gastrointestinal health.

• Assess renal function: avoid use if severe renal impairment is present.
• Verify calcium/vitamin D intake: ensure adequate supplementation to reduce hypocalcaemia risk.
• Review esophageal disorders: patients with active esophagitis should not take oral bisphosphonates.
• Counsel on administration: swallow tablet with a full glass of water, remain upright for at least 30 minutes.
• Monitor for atypical fractures: advise patients to report any new thigh or groin pain.
• Store at ambient temperature: keep in the original container, protect from moisture and direct sunlight.

Alendronate sodium can interact with several medicines that affect calcium balance or gastrointestinal absorption.

Major Interactions (Avoid)

• Calcium‑containing antacids: reduce alendronate absorption; separate dosing by at least 30 minutes.
• Proton‑pump inhibitors (e.g., omeprazole): may diminish drug bioavailability.
• Oral bisphosphonates taken concurrently: increase risk of gastrointestinal irritation.

Moderate Interactions (Monitor Closely)

• Corticosteroids: may exacerbate bone loss, requiring closer monitoring of bone density.
• Loop diuretics (e.g., furosemide): can predispose to hypocalcaemia; monitor serum calcium.
• Vitamin D analogues: adjust dosing to avoid hypercalcemia when combined with high‑dose vitamin D.