[Drug clinics. The drug of the month. Alendronate (Fosamax)].

Alendronate (Fosamax, Merck Sharp & Dohme) is an aminobisphosphonate which inhibits bone turnover by suppressing the activity of osteoclasts without increasing the risk of osteomalacia. Alendronate is highly effective at preventing bone loss associated to absence of endogenous estrogen and induces a sustained increase in bone mass. Fosamax is indicated and reimbursed in the treatment of osteoporosis in postmenopausal women, with either an history of bone fracture confirmed by X-ray exam or obvious osteoporosis assessed by bone mineral density measurement. The recommended dosage is 10 mg once daily, continuously. The drug should be absorbed after an overnight fast to improve its bioavailability and with a big glass of plain water to reduce the risk of oesophageal ulcerations. Large randomized controlled trials for up to 3 years have demonstrated that alendronate is able to reduce the risk and rate of occurrence of vertebral and nonvertebral fractures in postmenopausal women.