Fosamax and Osteonecrosis of the Jaw: Evaluating the Evidence for Risk and Causation

Latest update (2026-05)

FDA enforcement record (Ongoing): This recall is being conducted due to out of specification assay results in a limited number of bottles that were stored on side. [source]

From General Health Science to Targeted Risk Assessment

The legacy of general health and science information has long served as a foundation for public understanding of medical risks, often drawing from large-scale population studies to inform preventive care. In this tradition, broad health contexts—such as cardiovascular disease prevention—have relied on randomized trials to evaluate interventions like low-dose aspirin, where outcomes are measured against composite endpoints. This heritage emphasizes the importance of rigorous methodology in assessing risk-benefit profiles across diverse populations. Transitioning from this general health framework, a parallel need emerges to examine specific exposures in occupational and therapeutic settings. One such area involves the long-term use of bisphosphonate medications, particularly Fosamax, and its association with osteonecrosis of the jaw. While the initial health context focused on systemic disease prevention, the pivot here shifts attention to localized adverse effects linked to drug exposure. This transition requires applying the same scientific rigor—rooted in epidemiological principles—to understand risk factors, dosage duration, and patient susceptibility. By moving from broad health inquiries to targeted exposure concerns, the analysis maintains a neutral, evidence-based approach, ensuring that occupational and therapeutic risk assessments are grounded in the same standards of objectivity that defined earlier health science communications.

Understanding Fosamax and Its Mechanism

Fosamax (alendronate) is a bisphosphonate medication approved for the treatment and prevention of osteoporosis in postmenopausal women, treatment to increase bone mass in men with osteoporosis, treatment of glucocorticoid-induced osteoporosis, and treatment of Paget's disease of bone (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). Its mechanism involves increasing bone mass and reducing fracture incidence, including hip and spine fractures (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). However, a known adverse effect associated with bisphosphonates, including Fosamax, is osteonecrosis of the jaw (ONJ). ONJ is a condition characterized by exposed, non-healing bone in the jaw, which can occur spontaneously but is generally associated with tooth extraction and/or local infection with delayed healing (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). The clinical presentation often involves pain, swelling, and exposed bone in the oral cavity, and diagnosis is typically based on clinical examination and imaging. The condition has been reported in patients taking bisphosphonates, including Fosamax and Fosamax Plus D (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56; https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1).

Mechanistic Pathways and Risk Factors for ONJ

The mechanistic pathways linking Fosamax to ONJ are not fully elucidated, but research suggests that bisphosphonates suppress bone turnover by inhibiting osteoclast activity, which may impair the jawbone's ability to remodel and heal after minor trauma or infection. A multiscale characterization of jawbone provides comprehensive information that can help better understand jawbone-specific responses to bone-related complications, including bisphosphonate-related osteonecrosis of the jaw (https://pubmed.ncbi.nlm.nih.gov/40345077/). This indicates that the jawbone's unique structure and physiology may make it particularly susceptible to the effects of bisphosphonates. Risk factors for ONJ 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 (e.g., periodontal and/or other pre-existing dental disease, anemia, coagulopathy, infection, ill-fitting dentures) (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1). The risk of ONJ may increase with duration of exposure to bisphosphonates (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1). For patients requiring invasive dental procedures, discontinuation of bisphosphonate treatment may reduce the risk for ONJ (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1).

Epidemiological Evidence and Risk Quantification

Regarding the timeline between exposure and documented harm, the time to onset of symptoms varied from one day to several months after starting the drug (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). Most patients had relief of symptoms after stopping, but a subset had recurrence of symptoms when rechallenged with the same drug or another bisphosphonate (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). In placebo-controlled clinical studies of Fosamax, the percentages of patients with these symptoms were similar in the Fosamax and placebo groups (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). This suggests that while ONJ is a recognized adverse effect, its incidence in osteoporosis patients is low. A cohort study among cancer-free female patients aged 40-89 with, or at risk for, osteoporosis in the United Kingdom Clinical Practice Research Datalink found that ONJ risk was threefold higher after 2-3 years of treatment and eightfold after 10 years compared with past use (https://pubmed.ncbi.nlm.nih.gov/39400702/). Absolute risks remained low, approximately 0.05% after 5 years, and diminished after discontinuation (https://pubmed.ncbi.nlm.nih.gov/39400702/). This study underscores that while the relative risk increases with longer exposure, the absolute risk remains small.

Adequacy of Warnings and Causation Considerations

The adequacy of warnings regarding Fosamax and ONJ is addressed in the prescribing information. The label includes a specific warning under "Warnings and Precautions" (Section 5.4) that describes ONJ, its association with bisphosphonates, and known risk factors (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56; https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1). The label also advises discontinuation if severe symptoms develop and notes that most patients had relief after stopping (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). For patients requiring invasive dental procedures, discontinuation of bisphosphonate treatment may reduce the risk for ONJ (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1). Causation-related considerations for affected patients involve evaluating the temporal relationship between Fosamax use and ONJ onset, excluding other causes such as cancer or concurrent medications, and assessing risk factors. The label notes that ONJ can occur spontaneously and is generally associated with dental procedures or infections (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). The recurrence of symptoms upon rechallenge with bisphosphonates supports a causal link (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56). However, the low absolute risk and the similarity in symptom rates between Fosamax and placebo groups in clinical trials complicate individual causation assessments (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56).

Important Notice

This page is for educational and informational purposes only. It does not provide medical diagnosis, treatment, or legal advice. Consult licensed clinicians and qualified attorneys for case-specific decisions.

Frequently Asked Questions

What is the link between Fosamax and osteonecrosis of the jaw?

Fosamax (alendronate) is a bisphosphonate that can increase the risk of osteonecrosis of the jaw (ONJ), a condition where the jawbone fails to heal after minor trauma. The risk is higher with longer use and in patients with risk factors such as invasive dental procedures. Studies show that while the relative risk increases with duration, the absolute risk remains low (e.g., about 0.05% after 5 years). (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56; https://pubmed.ncbi.nlm.nih.gov/39400702/)

How long does it take for Fosamax to cause jaw problems?

The time to onset of ONJ symptoms can vary from one day to several months after starting Fosamax. Most patients experience relief after stopping the drug, but symptoms may recur if rechallenged with the same or another bisphosphonate. (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=14e931fd-2c5f-4d90-b7db-5980706f4a56)

What are the risk factors for developing ONJ while taking Fosamax?

Risk factors include invasive dental procedures (e.g., tooth extraction, implants), cancer diagnosis, concomitant therapies (chemotherapy, corticosteroids, angiogenesis inhibitors), poor oral hygiene, and pre-existing dental disease. The risk increases with longer duration of bisphosphonate use. (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1)

Can stopping Fosamax reduce the risk of ONJ?

Yes, for patients requiring invasive dental procedures, discontinuation of bisphosphonate treatment may reduce the risk of ONJ. The prescribing information advises considering drug discontinuation before such procedures. (https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10307e7e-9a84-4aa1-8c5c-4b209cffe4d1)

Does submitting information create an attorney-client relationship?

No. Submission requests an initial records screening only and does not create an attorney-client relationship.

Information Registry: individuals with documented Fosamax exposure and a confirmed Osteonecrosis of the Jaw diagnosis may request an independent eligibility review. [Begin Assessment]

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This page is for educational and informational purposes only and is not medical or legal advice. Consult a licensed professional for case-specific guidance.