Top 300 Pharmacy Drug Cards

ALENDRONATE: Fosamax, Various

Class: Bisphosphonate

Dosage Forms. Tablet: 5 mg, 10 mg, 35 mg, 40 mg, 70 mg; Solution: 70 mg/75 mL; Effervescent Tablet: 70 mg

Common FDA Label Indication, Dosing, and Titration.

1. Postmenopausal osteoporosis: 70 mg po once weekly or 10 mg po daily

2. Postmenopausal osteoporosis, prophylaxis: 5 mg po daily, or 35 mg po once weekly

3. Paget disease: 40 mg po daily for 6 mo

4. Osteoporosis, male: 10 mg once daily or 70 mg once weekly

5. Glucocorticoid-induced osteoporosis in those with daily dosage ≥7.5 mg of prednisone (or equivalent): 5 mg once daily; a dose of 10 mg once daily should be used in postmenopausal females who are not receiving estrogen

Off-Label Uses. None

MOA. Alendronate binds to bone hydroxyapatite, and at the cellular level, inhibits osteoclast activity, thereby modulating bone metabolism.


Drug Characteristics: Alendronate


Medication Safety Issues: Alendronate


Drug Interactions: Alendronate


Adverse Reactions: Alendronate


Efficacy Monitoring Parameters. Increased bone mineral density, decreased incidence of bone fractures.

Toxicity Monitoring Parameters. Baseline serum creatinine, calcium, phosphorous, severe skin rash, difficulty swallowing, swelling, tooth problems, severe pain.

Key Patient Counseling Points. Swallow the non-effervescent tablet whole with a large glass (8 oz) of plain water only. Dissolve one effervescent tablet in 4 oz of room temperature plain water only (not mineral water or flavored water); once effervescence stops, wait ≥5 min and stir the solution for ~10 s and then drink. Wait at least 30 min after you swallow the tablet before you eat or drink anything or take any other medicines. This will help your body absorb the medicine. Do not lie down for at least 30 min after taking this medicine, and do not lie down until after you have eaten some food.

Clinical Pearls. Concurrent chemotherapy and poor oral hygiene increase the risk of osteonecrosis of the jaw. Atypical fractures of the thigh have been reported in patients taking bisphosphonates for osteoporosis; discontinue therapy in patients who develop evidence of a femoral shaft fracture. Adequate calcium and vitamin intake required for efficacy. Men and women ≥50 y of age should consume 1200-1500 mg of elemental calcium and 800-1000 units of vitamin D daily.

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