OpenClaim

Alendronate Side Effects

The most commonly reported side effects of alendronate include pain, fatigue, and alopecia, based on 101,765 FDA adverse event reports from 2004 to 2025. 11.1% of reports found the drug to be ineffective.

Alendronate side effects

Percentages show how often each reaction appears relative to total reports for alendronate.

1
Pain12.3%12,479
2
Fatigue11.3%11,540
3
Drug Ineffective11.1%11,254
4
Alopecia9.5%9,620
5
Rheumatoid Arthritis9.4%9,589
6
Abdominal Discomfort9.4%9,578
7
Arthralgia9.3%9,506
8
Systemic Lupus Erythematosus8.8%8,943
9
Pemphigus8.6%8,705
10
Rash8.0%8,143
11
Glossodynia7.9%8,045
12
Arthropathy7.3%7,457
13
Swelling7.3%7,412
14
Femur Fracture7.3%7,402
15
Off Label Use7.2%7,361

These are voluntary reports and do not establish that alendronate caused these reactions.

Report severity

78.4%Serious79,798 reports
37.1%Hospitalizations37,752 reports
11.1%Fatal11,339 reports

Seriousness is determined by the reporter, not by OpenClaim.

Alendronate drug interactions

Other drugs that appear in adverse event reports alongside alendronate. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Adalimumab16.0%16,307
2
Etanercept13.9%14,161
3
Methotrexate13.4%13,686
4
Prednisone12.9%13,140
5
Rituximab12.8%13,069
6
Infliximab12.7%12,891
7
Abatacept12.6%12,848
8
Tocilizumab12.4%12,584
9
Leflunomide12.0%12,195
10
Hydroxychloroquine-sulfate11.6%11,835
11
Folic-acid11.1%11,311
12
Certolizumab-pegol10.9%11,125
13
Cetirizine-hydrochloride10.3%10,483
14
Sulfasalazine10.3%10,435
15
Golimumab10.2%10,421

Taken alongside

1
Ergocalciferol14.9%15,185
2
Acetaminophen14.1%14,306
3
Calcium13.5%13,767
4
Prednisone12.9%13,098
5
Levothyroxine-sodium11.3%11,484
6
Aspirin10.8%11,017
7
Pantoprazole-sodium8.8%9,004
8
Folic-acid8.4%8,506
9
Omeprazole8.3%8,469
10
Atorvastatin-calcium7.7%7,803
11
Lisinopril7.2%7,325
12
Methotrexate6.9%7,032
13
Furosemide6.8%6,887
14
Albuterol6.7%6,812
15
Amlodipine6.6%6,674

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports alendronate side effects

78.4% of alendronate adverse event reports involve female patients and 12.5% involve male patients. The largest age group is elderly at 55%. These figures reflect who reports side effects, not underlying risk.

Sex

Female78.4%
Male12.5%
Unknown9.1%

Age group

< 20.2%
2–110.1%
12–170.2%
18–6444.0%
65+55.5%

What is alendronate used for

Conditions and purposes for which patients were taking alendronate when the adverse event was reported.

Abdominal DiscomfortAbdominal DistensionAbdominal Pain UpperAccidental Exposure To ProductAcquired HaemophiliaAddison^s DiseaseAdjuvant TherapyAdrenocortical Steroid TherapyAdverse Drug ReactionAdverse EventAdverse ReactionAlopeciaAnaemiaAnaphylactic ReactionAngina Pectoris

Showing 15 of 596 indications

Alendronate brand names and reporting trend

Alendronate is sold under the brand name Fosamax.

Brand names

Fosamax64,246

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking alendronate with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.