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 in patients with creatinine clearance <35 mL/min/1.73 m² - The American Journal of Kidney Diseases specifically recommends against use below this threshold 2
- Intravenous bisphosphonates should not be used with creatinine clearance <30 mL/min due to risk of acute renal failure, though oral alendronate has better renal safety 4, 3
Vitamin D Deficiency
- Correct vitamin D deficiency before starting therapy - Target serum 25(OH)D ≥30 ng/mL to prevent hypocalcemia, particularly important as hypocalcemia has been reported in patients with unrecognized deficiency 4, 2, 3
- For levels <30 ng/mL, use ergocalciferol 50,000 IU weekly for 8 weeks, then recheck 2
Recent Dental Procedures
- Consider delaying initiation in patients who recently underwent dental extractions - Due to rare but serious risk of osteonecrosis of the jaw (ONJ), though incidence with osteoporosis dosing is very low (<1-10 per 100,000 person-years) 4, 3
- Dental examination and prophylactic measures should be considered before starting therapy 4
Increased Aspiration Risk
- Patients at increased risk of aspiration should not receive alendronate 3
Critical Administration Requirements
These are not contraindications per se, but failure to follow these instructions creates contraindications:
- Must take with at least 6-8 oz of plain water only 1
- Must take at least 30 minutes before first food, beverage, or other medication of the day 1
- Must remain fully upright (standing or sitting) for at least 30 minutes after dosing 1
Common pitfall: Esophageal ulceration cases have been attributed to noncompliance with these administration requirements rather than the drug itself 5. Proper patient education on administration technique is essential to prevent serious upper GI complications.