What are the contraindications for Fosamax (alendronate)?

Fosamax (Alendronate) Contraindications

Fosamax is absolutely contraindicated in patients who cannot stand or sit upright for at least 30 minutes, those with esophageal abnormalities that delay emptying, hypocalcemia, and hypersensitivity to any component of the product. 1

Absolute Contraindications

The FDA label and clinical guidelines identify four absolute contraindications where Fosamax must not be used:

• Inability to stand or sit upright for at least 30 minutes - This is critical to prevent esophageal complications including ulceration 2, 3, 1
• Esophageal abnormalities that delay esophageal emptying - Patients with conditions like achalasia, strictures, or severe motility disorders are at high risk for pill esophagitis 4, 2, 3
• Hypocalcemia - Must be corrected before initiating therapy to prevent worsening calcium deficiency 2, 3, 1
• Hypersensitivity to alendronate or any component - Including documented urticaria or angioedema reactions 1

Relative Contraindications and Major Precautions

Renal Impairment

• Avoid oral alendronate in patients with creatinine clearance < 35 mL/min/1.73 m² 2
• Never use intravenous bisphosphonates with creatinine clearance < 30 mL/min due to risk of acute renal failure 4, 3
• Oral formulations have better renal safety profiles than IV bisphosphonates in patients with reduced kidney function 4

Vitamin D Deficiency

• Correct vitamin D deficiency before starting alendronate, particularly before IV formulations, to prevent severe hypocalcemia 4, 3
• Target serum 25(OH)D levels ≥30 ng/mL before initiating therapy 2
• For levels <30 ng/mL, treat with ergocalciferol 50,000 IU weekly for 8 weeks, then recheck 4, 2

Dental Considerations

• Consider delaying initiation in patients who recently underwent dental extractions or invasive dental procedures due to osteonecrosis of the jaw (ONJ) risk 3
• Perform dental examination and complete necessary dental work before starting therapy 4
• ONJ risk with osteoporosis-dose alendronate is very low (<1-10 per 100,000 person-years) but increases with duration beyond 2 years 2

Gastrointestinal Risk Factors

• Use extreme caution in patients with active upper GI problems including esophagitis, gastritis, or peptic ulcer disease 4
• Patients at increased risk of aspiration should not receive alendronate 3
• Upper GI adverse events (abdominal pain, dyspepsia, nausea) are the most common side effects, though serious esophageal ulceration is rare when dosing instructions are followed 5, 6

Essential Co-Administration Requirements

While not contraindications per se, these are mandatory for safe use:

• All patients must receive adequate calcium (1,000-1,200 mg daily) and vitamin D (800-1,000 IU daily) supplementation 4, 2
• Inadequate supplementation reduces treatment efficacy and increases hypocalcemia risk 2

Clinical Pitfalls to Avoid

• Most esophageal complications occur due to noncompliance with administration instructions (not taking with full glass of water, lying down within 30 minutes) 5
• Do not assume normal vitamin D status - always check 25(OH)D levels before initiating therapy 4, 3
• In patients discontinuing denosumab, do not abruptly stop without considering sequential alendronate to prevent rebound vertebral fractures 2