alendronate (Fosamax, Binosto, Fosamax Plus D)
Classes: Calcium Metabolism Modifiers; Bisphosphonate Derivatives
Dosing and uses of Fosamax, Binosto (alendronate)
Adult dosage forms and strengths
tablet
- 5mg
- 10mg
- 35mg
- 40mg
- 70mg
tablet for solution (effervescent)
- 70mg
solution, oraL
- 70mg/75mL
Osteoporosis
Prevention in postmenopausal women
- 5 mg PO once daily or 35 mg PO once weekly
Treatment in postmenopausal women and men
- 10 mg PO once daily or 70 mg PO once weekly
Glucocorticoid-Induced Osteoporosis
Males and females: 5 mg PO once daily (10 mg/day for postmenopausal women not on hormone replacement therapy)
Paget Disease
40 mg/day PO for 6 months
Dosing Modifications
Mild-to-moderate renal impairment (CrCl 35-60 mL/min): Dose adjustment not necessary
Severe renal impairment (CrCl <35 mL/min): Not recommended
Administration
Take only in morning, not at bedtime or before arising
Take tablet with full glass of water (6-8 oz) at least 30 minutes before first food or drink of day, in upright position
Administer oral solution with at least 2 ounces of water
Swallow with plain water only; mineral water, coffee, juice or other beverages severely reduces bioavailability
Swallow tablet whole; do not suck or chew
Do not lie down for 30 minutes after taking drug; sit or stand upright
Despite long terminal half-life (10 years), bone-incorporated drug is not pharmacologically active
If dietary intake is inadequate, patients should receive calcium supplement and vitamin d
Limitation of Use
Optimal duration of use not determined; for patients at low-risk for fracture, consider drug discontinuation after 3-5 years of use
Pediatric dosage forms and strengths
Safety and efficacy not established
Osteogenesis Imperfecta (Orphan)
Treatment in pediatric patients aged 4 years or older
Orphan indication sponsor
- Merck, Sharpe & Dohme Corp; 126 East Lincoln Ave, PO Box 2000; Rahway, NJ 07065-0900
Gaucher Disease (Orphan)
Treatment of bone manifestations of disease
Orphan indication sponsor
- Richard J Wenstrup, MD; Division of Human Genetics, Children's Hospital Research Foundation; Cincinnati, OH 45229-3039
Fosamax, Binosto (alendronate) adverse (side) effects
>10%
Hypocalcemia, transient and mild (18%)
1-10%
Hypophosphatemia, transient and mild (10%)
Abdominal pain (7%)
Musculoskeletal pain (4.1%)
Dyspepsia (3.6%)
Nausea (3.6%)
Constipation (3.1%)
Diarrhea (3.1%)
Flatulence (2.6%)
Headache (2.6%)
Acid regurgitation (2%)
Esophagitis (1.5%)
Abdominal distention (1%)
<1%
Alopecia
Diaphyseal femur fracture
Esophageal cancer
Flulike syndrome
Gastritis
Myalgia
Oropharyngeal ulceration
Pruritus
Rash
Taste perversion
Toxic epidermal necrolysis
Uveitis
Vertigo
Weakness
Postmarketing Reports
Body as a whole: Hypersensitivity reactions including urticaria and angioedema; transient myalgia, malaise, asthenia, and fever; symptomatic hypocalcemia; peripheral edema
Gastrointestinal: Esophagitis, esophageal erosions, esophageal ulcers, esophageal stricture or perforation, and oropharyngeal ulceration; gastric or duodenal ulcers
Localized osteonecrosis of the jaw, generally associated with tooth extraction and/or local infection with delayed healing
Musculoskeletal: Bone, joint, and/or muscle pain, occasionally severe, and incapacitating; joint swelling; low-energy femoral shaft and subtrochanteric fractures
Nervous system: dizziness, vertigo
Pulmonary: Acute asthma exacerbations
Skin: Rash (occasionally with photosensitivity), pruritus, alopecia, severe skin reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis
Special Senses: Uveitis, scleritis, or episcleritis, cholesteatoma of the external auditory canal (focal osteonecrosis)
Warnings
Contraindications
Hypersensitivity
Hypocalcemia
Abnormalities of the esophagus delaying esophageal emptying such as stricture or achalasia
Inability to stand or sit upright for 30 minutes
Cautions
May cause local irritation of upper GI mucosa
Take with plain water only, not coffee, juice, or mineral water; sit or stand upright for at least 30 minutes after administration
Hypocalcemia reported with use of bisphosphonates; correct hypocalcemia prior to therapy; ensure adequate calcium and vitamin D intake
Conjunctivitis, uveitis, episcleritis, and scleritis reported with alendronate use; perform ophthalmic evaluation in patients with signs of ocular inflammation
Avoid concomitant polyvalent cation-containing medications
Osteonecrosis of the jaw, can occur spontaneously and is generally associated with tooth extraction and/or local infection with delayed healing; known risk factors include invasive dental procedures (e.g., tooth extraction, dental implants, boney surgery), diagnosis of cancer, concomitant therapies (e.g., chemotherapy, corticosteroids, angiogenesis inhibitors), poor oral hygiene, and co-morbid disorders; risk of osteonecrosis of the jaw may increase with duration of exposure to bisphosphonates
Not recommended in severe renal impairment (CrCl <35 mL/min)
In Paget disease, drug is available only through Paget's Patient Support Program with Pharma Care Specialty Pharmacy (800-238-7828 x58197) distribution system for 40-mg dosage regimen
Risk of severe bone, joint, or muscle pain; discontinue therapy in patients who experience severe symptoms of pain; avoid use in patients with history of these symptoms in association with bisphosphonate therapy
Possible increased risk of atypical subtrochanteric and diaphyseal femur fractures; may consider discontinuing therapy after 3-5 years in patients at low-risk for fracture; following discontinuation, re-evaluate fracture risk periodically; consider periodic reevaluation of need for continued bisphosphonate therapy, particularly if treatment lasts >5 years; patients with new thigh or groin pain should be evaluated to rule out a femoral fracture
Use effervescent tablet with caution in sodium-restricted patients (tablet contains 650 mg of sodium)
Esophageal cancer risk (July 21, 2011, FDA safety communication)
- Conflicting findings exist from studies evaluating risk of esophageal cancer with oral bisphosphonates
- Esophagitis, dysphagia, esophageal ulcers, esophageal erosions, and esophageal stricture reported with oral bisphosphonates; risk is higher in patients unable to closely follow dosing instructions (eg, sitting up or standing after administration and taking with full glass of water); use with caution in patients with dysphagia, esophageal disease, gastritis, duodenitis, or ulcers; discontinue use if new or worsening symptoms develop
- An ongoing review of data from published studies to evaluate whether use of oral bisphosphonates is associated with an increased risk of cancer of the esophagus is currently being conducted by FDA
- FDA has not concluded that taking an oral bisphosphonate increases risk of esophageal cancer
- Data are insufficient to recommend endoscopic screening of asymptomatic patients
- FDA will continue to evaluate all available data supporting safety and effectiveness of bisphosphonates and will update public when more information becomes available
- Instruct patients to contact their healthcare provider if they develop symptoms of esophagitis (eg, swallowing difficulties, chest pain, new or worsening heartburn, trouble or pain when swallowing)
Pregnancy and lactation
Pregnancy category: C
Lactation: Unknown whether drug is excreted in milk; use with caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Fosamax, Binosto (alendronate)
Mechanism of action
Bisphosphonate; binds to hydroxyapatite crystals in bone and inhibits osteoclast-mediated bone resorption; decreases mineral release and collagen or matrix breakdown in bone
Absorption
Bioavailability (fasting): Women, 0.64%; men, 0.59%; reduced up to 60% by food
Onset: 3 weeks
Duration: 12-30 weeks (multiple doses)
Distribution
Protein bound: 78%
Vd: 28 L (exclusive of bone)
Metabolism
Not metabolized
Elimination
Half-life: Up to 10 years in bone (terminal)
Excretion: Urine 50%, feces (unabsorbed drug)