alendronate sodium

alendronate sodium

(ah len' dro nate)

Fosamax

Pregnancy Category C

Drug classes

Bisphosphonate

Calcium regulator

Therapeutic actions

Slows normal and abnormal bone resorption without inhibiting bone formation and mineralization.

Indications

·        Treatment and prevention of osteoporosis in postmenopausal women

·        Treatment of men with osteoporosis

·        Treatment of glucocorticoid-induced osteoporosis

·        Treatment of Paget's disease of bone in patients with alkaline phosphatase at least two times upper limit of normal, those who are symptomatic, those at risk for future complications

Contraindications and cautions

·        Contraindicated with allergy to biphosphonates; hypocalcemia.

·        Use cautiously with renal dysfunction, upper GI disease, pregnancy, lactation.

Available forms

Tablets—5, 10, 35, 40, 70 mg; oral solution—70 mg

Dosages

ADULTS

·        Postmenopausal osteoporosis: 10 mg/day PO in AM with full glass of water, at least 30 min before the first beverage, food, or medication of the day, or 70 mg PO once a week or one bottle of 70-mg oral solution once a week. Avoid lying down for 30 min after taking drug.

·        Males with osteoporosis: 10 mg/day PO or 70-mg tablet or one bottle 70-mg oral solution once a week.

·        Prevention of osteoporosis: 5 mg/day PO or 35 mg PO once a week.

·        Paget's disease: 40 mg/day PO in AM with full glass of water, at least 30 min before the first beverage, food, or medication of the day for 6 mo; may retreat after 6-mo treatment-free period.

·        Glucocorticoid-induced osteoporosis: 5 mg/day PO with calcium and vitamin D; 10 mg/day PO for postmenopausal women not on estrogen.

PEDIATRIC PATIENTS

Safety and efficacy not established.

PATIENTS WITH RENAL IMPAIRMENT

Dosage adjustment not necessary for creatinine clearance 35–60 mL/min; not recommended if creatinine clearance < 35 mL/min.

Pharmacokinetics

Route	Onset	Duration
Oral	Slow	Days

Metabolism: Not metabolized; T_1/2: More than 10 yr

Distribution: Crosses placenta; may enter breast milk

Excretion: Urine

Adverse effects

·        CNS: Headache

·        GI: Nausea, diarrhea, GI irritation, pain, esophageal erosion

·        Skeletal: Increased or recurrent bone pain, focal osteomalacia

Interactions

Drug-drug

·        Increased risk of GI distress with aspirin

·        Decreased absorption if taken with antacids, calcium, iron, multivalent cations; separate dosing by at least 30 min

Drug-food

·        Significantly decreased absorption and serum levels if taken with food; separate dosing from food and beverage by at least 30 min

Nursing considerations

CLINICAL ALERT!

Name confusion has occurred between Fosamax (alendronate) and Flomax (tamsulosin); use caution.

Assessment

·        History: Allergy to bisphosphonates, renal failure, upper GI disease, lactation, pregnancy

·        Physical: Muscle tone, bone pain; bowel sounds; urinalysis, serum calcium

Interventions

·        WARNING: Give in AM with full glass of water at least 30 min before the first beverage, food, or medication of the day. Patient must stay upright for 30 min to decrease risk of potentially serious esophageal erosion.

·        Monitor serum calcium levels before, during, and after therapy.

·        Ensure 6-mo rest period after treatment for Paget's disease if retreatment is required.

·        Ensure adequate vitamin D and calcium intake.

·        Provide comfort measures if bone pain returns.

Teaching points

·        Take drug in morning with a full glass of plain water (not mineral water), at least 30 minutes before any beverage, food, or medication, and stay upright for 30 minutes and until after the first food of the day; mark calendar for once weekly dosing.

·        You may experience these side effects: Nausea, diarrhea; bone pain, headache (analgesic may help).

·        Report twitching, muscle spasms, dark-colored urine, severe diarrhea, difficulty swallowing.

Adverse effects in Italic are most common; those in Bold are life-threatening.