alendronate Side Effects
Also known as: Fosamax
Analysis of 98,033 adverse event reports submitted to the FDA from 2003 to 2025.
Total Reports
98,033
Death-Related
11,123
11.3% of reports
Hospitalizations
36,609
37.3% of reports
Top Indication
Osteoporosis
Most Reported Adverse Reactions
Who Reports Side Effects
Gender Distribution
Age Distribution
Reporting Trend by Year
Reactions in Death Reports
Top reactions reported in 11,123 reports where death was an outcome. These are voluntarily reported and do not establish causation.
| Reaction | Reports |
|---|---|
| DEATH | 2,940 |
| FATIGUE | 2,297 |
| HYPERTENSION | 2,233 |
| GENERAL PHYSICAL HEALTH DETERIORATION | 2,175 |
| SYSTEMIC LUPUS ERYTHEMATOSUS | 2,129 |
| TYPE 2 DIABETES MELLITUS | 2,102 |
| GLOSSODYNIA | 2,095 |
| OFF LABEL USE | 2,091 |
| RHEUMATOID ARTHRITIS | 2,088 |
| ARTHRALGIA | 2,061 |
| HYPOAESTHESIA | 2,058 |
| INFUSION RELATED REACTION | 2,045 |
| HAND DEFORMITY | 2,040 |
| RASH | 2,028 |
| FIBROMYALGIA | 2,018 |
| PSORIATIC ARTHROPATHY | 2,017 |
| DUODENAL ULCER PERFORATION | 1,996 |
| WOUND | 1,994 |
| HELICOBACTER INFECTION | 1,989 |
| DIARRHOEA | 1,982 |
Reactions in Hospitalization Reports
Top reactions in 36,609 reports where hospitalization was an outcome.
| Reaction | Reports |
|---|---|
| FEMUR FRACTURE | 6,662 |
| FALL | 6,341 |
| ARTHRALGIA | 5,721 |
| HYPERTENSION | 5,409 |
| FATIGUE | 5,117 |
| PAIN | 5,096 |
| OSTEOARTHRITIS | 4,674 |
| DYSPNOEA | 4,329 |
| DRUG INEFFECTIVE | 4,291 |
| RHEUMATOID ARTHRITIS | 4,199 |
| NAUSEA | 4,122 |
| ARTHROPATHY | 3,901 |
| DIARRHOEA | 3,890 |
| RASH | 3,877 |
| OFF LABEL USE | 3,809 |
| PAIN IN EXTREMITY | 3,777 |
| PNEUMONIA | 3,774 |
| HEADACHE | 3,746 |
| IMPAIRED HEALING | 3,584 |
| DEPRESSION | 3,553 |
Nearby — Related Medications
What the FAERS Data Reveals About alendronate Side Effects
The FDA Adverse Event Reporting System (FAERS) contains 98,033 voluntary reports linked to alendronate and its brand equivalents (Fosamax), spanning 2003 through 2025. Of those, 11,123 (11.3%) listed death as an outcome and 36,609 (37.3%) involved hospitalization. The most common indication reported alongside adverse events was Osteoporosis.
Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 86% were female and 14% male; age distribution skews toward 45-64, with 18,310 reports in that bracket. The single most reported reaction is pain with 13,527 submissions, followed by fatigue and drug ineffective.
FAERS is a signal-detection tool, not a scorecard. Reports are voluntary, and a single case may list multiple suspect drugs, so numbers above should not be read as incidence rates or per-patient risk. Widely prescribed drugs naturally accumulate more reports than niche therapies even when individual risk is low. These aggregates are useful for spotting patterns that merit further pharmacovigilance, not for choosing between medications. This page is for educational reference only and is not medical advice — speak with a licensed clinician about any side-effect concerns.
Read our methodology — how this data is sourced, computed, and verified.