Reported Reactions

Drugs › Bisphosphonate

Brand name · Alendronate sodium

Fosamax: adverse event reports filed with FDA

34,844 reports list it as a suspect or interacting product, 2004–2026. Class: Bisphosphonate. Also reported as Fosamax Tablet, Fosamax 70mg, Fosamax 10mg.

34,844
reports as suspect product
0.2% of all reports · about 1,549 a year
1,311
reports, 12 months to June 2026
1,931 in the 12 months before
92.2%
marked serious by the reporter
90.3% across the class
15%
record death among outcomes, as reported
5,223 reports · not verified by FDA

34,844 adverse event reports received by FDA list the brand name Fosamax (alendronate sodium) as a suspect or interacting product, from January 2004 to June 2026. A further 24,084 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 1,311 reports listed it, down 32% from 1,931 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 1,549 reports a year and 0.2% of the 20,646,523 reports in the database, and 35.9% of the reports for the bisphosphonate class. How many people take it is not in the data, so a count is not a rate of occurrence.

Reporters most often recorded femur fracture (28.4%), pain (23.3%) and fatigue (19.9%). A report can list several reactions, so shares add to more than 100%; 3,673 different terms appear across these reports. Femur fracture is recorded in 28.4% of these reports, a larger share than in the median bisphosphonate drug (7.1%).

92.2% of the reports are marked serious by the reporter (90.3% across the class); 15% record death among the outcomes and 44.1% record hospitalisation, as reported. 33.2% of the reports came from other health professionals, and the largest patient age group is 45 to 64 (15.5%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

0119237Jul 2021: 122Aug 2021: 122Sep 2021: 218Oct 2021: 132Nov 2021: 192Dec 2021: 2272022Jan 2022: 158Feb 2022: 101Mar 2022: 144Apr 2022: 165May 2022: 203Jun 2022: 164Jul 2022: 72Aug 2022: 115Sep 2022: 92Oct 2022: 143Nov 2022: 104Dec 2022: 2132023Jan 2023: 116Feb 2023: 88Mar 2023: 57Apr 2023: 84May 2023: 78Jun 2023: 45Jul 2023: 48Aug 2023: 75Sep 2023: 80Oct 2023: 84Nov 2023: 69Dec 2023: 942024Jan 2024: 122Feb 2024: 143Mar 2024: 152Apr 2024: 154May 2024: 234Jun 2024: 188Jul 2024: 214Aug 2024: 113Sep 2024: 149Oct 2024: 200Nov 2024: 237Dec 2024: 2262025Jan 2025: 115Feb 2025: 171Mar 2025: 203Apr 2025: 77May 2025: 26Jun 2025: 200Jul 2025: 202Aug 2025: 160Sep 2025: 144Oct 2025: 84Nov 2025: 102Dec 2025: 1772026Jan 2026: 76Feb 2026: 88Mar 2026: 45Apr 2026: 92May 2026: 38Jun 2026: 103

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

02,6015,2022004: 63420042005: 1,1272006: 1,3492007: 2,04720072008: 1,4182009: 1,1722010: 1,45820102011: 2,2102012: 5,2022013: 2,53420132014: 1,4042015: 1,0022016: 65820162017: 6942018: 5912019: 90620192020: 1,2152021: 2,3962022: 1,67420222023: 9182024: 2,1322025: 1,66120252026: 442

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Fosamax reports recording the termmedian drug in bisphosphonate

  1. Femur fracture28.4%9,901
  2. Painpain, site not specified23.3%8,130
  3. Fatiguetiredness19.9%6,949
  4. Abdominal discomfortstomach discomfort19.5%6,790
  5. Alopeciahair loss19.5%6,782
  6. Systemic lupus erythematosuslupus, an autoimmune disease19.4%6,758
  7. Drug ineffectivethe medicine did not work as expected19.4%6,754
  8. Rheumatoid arthritisrheumatoid arthritis, an inflammatory joint disease19.3%6,725
  9. Pemphigus18.8%6,561
  10. Arthralgiajoint pain17.9%6,235
  11. Glossodynia17.2%5,977
  12. Arthropathy16.5%5,762
  13. Hypertensionhigh blood pressure15.9%5,532
  14. Swellingswelling15.6%5,445
  15. Rashskin rash15.4%5,372
  16. Hand deformity14.4%5,012
  17. Wound13.9%4,852
  18. Falla fall13.4%4,684
  19. Osteoarthritis13.2%4,591
  20. Drug intolerancethe medicine was not tolerated13.1%4,567
  21. Infusion related reactiona reaction during or soon after an infusion13%4,547
  22. Joint swellinga swollen joint12.9%4,502
  23. Synovitis12.7%4,435
  24. Hypersensitivityan allergic-type reaction12.5%4,360
  25. Maternal exposure during pregnancythe mother took the medicine during pregnancy12.4%4,309
  26. Impaired healingslow healing12.1%4,231
  27. Pericarditisinflammation of the sac around the heart11.8%4,098
  28. Hepatic enzyme increasedraised liver enzymes11.6%4,052
  29. Off label useused for a purpose or in a way not on the label11.2%3,909

Top 30 of 3,673 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 9 drugs in the bisphosphonate class; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death15%5,223
Life-threatening14%4,881
Hospitalisation (initial or prolonged)44.1%15,357
Disability33.2%11,585
Congenital anomaly6.2%2,146
Other serious72.6%25,314
Not serious7.8%2,708

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 97,060 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20%10
2 to 110.1%27
12 to 170%13
18 to 4412.4%4,308
45 to 6415.5%5,400
65 to 7410.7%3,741
75 and over11%3,843
Age not given50.2%17,502

Patient sex

Female82.7%28,807
Male5.8%2,006
Not given11.6%4,031

Who reported

Physician23.3%8,118
Pharmacist1.8%640
Other health professional33.2%11,553
Lawyer8.2%2,860
Consumer or non-health professional27.7%9,660
Not given5.8%2,013

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 55.3% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Osteoporosis11,39332.7%
Rheumatoid arthritis6,28918%
Osteopenia2,3506.7%
Osteoporosis prophylaxis6751.9%
Bone density decreased2290.7%
Osteoporosis postmenopausal1530.4%

The indication field is filled in by the reporter and is often blank; shares are of all 34,844 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Fosamax reports
Prednisone9,81228.2%
Folic acid9,45327.1%
Methotrexate9,10926.1%
Orencia8,86725.4%
Cimzia8,76725.2%
Actemra8,71325%
Enbrel8,69725%
Arava8,57624.6%
Humira8,44924.2%
Sulfasalazine8,16823.4%

Other products listed in reports where Fosamax is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureFosamaxBisphosphonateAll reports
Reports as suspect product34,84497,06020,646,523
Share of that pool—35.9%0.2%
Reports, latest 12 months1,311—1,332,454
Marked serious92.2%90.3%57.4%
Death recorded among outcomes, per 1,000 reports15013891
Hospitalisation recorded, per 1,000 reports441369213
Consumer-filed share27.7%28%45.8%
Top term, share of reportsFemur fracture 28.4%median 7.1%0.1%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Other drugs in the bisphosphonate class

DrugName typeReportsLatest 12 monthsMarked serious
Alendronate sodiumgeneric18,0821,52890.4%
Zoledronic acidgeneric16,6821,86897.1%
Reclastbrand10,38240281%
Actonelbrand6,0393384.3%
Alendronatebrand4,04521379.6%
Risedronate sodiumgeneric3,51255292.5%
Pamidronate disodiumgeneric2,1363296.9%
Ibandronate sodiumgeneric1,3386071.5%

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." A brand and its generic are separate rows because reporters name them separately.

Questions about Fosamax reports

How many adverse event reports has FDA received for Fosamax?

34,844 reports list Fosamax as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 1,311 of them arrived in the latest 12 months. Another 24,084 list it only as a concomitant medication.

What reactions are recorded in Fosamax reports?

femur fracture (28.4%), pain (23.3%), fatigue (19.9%), abdominal discomfort (19.5%) and alopecia (19.5%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Fosamax was responsible.

How serious are the reports?

92.2% are marked serious by the reporter. Among the outcomes recorded, 15% of reports include death and 44.1% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

other health professional (33.2%), consumer or non-health professional (27.7%) and physician (23.3%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Fosamax rising?

1,311 reports in the 12 months to June 2026, down 32% from 1,931 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Fosamax was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Fosamax?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Fosamax as a suspect or interacting product; reports listing it only as a concomitant medication (24,084) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.