Reported Reactions

Drugs › Aminosalicylate

Generic name

Mesalamine: adverse event reports filed with FDA

8,961 reports list it as a suspect or interacting product, 2004–2026. Class: Aminosalicylate. Also reported as Mesalamine Delayed-Release Tablets, Mesalamine 1 2g, Mesalamine Delayed Release Tablets 1 2 G.

8,961
reports as suspect product
0% of all reports · about 398 a year
1,401
reports, 12 months to June 2026
1,728 in the 12 months before
92%
marked serious by the reporter
86.5% across the class
12.9%
record death among outcomes, as reported
1,152 reports · not verified by FDA

Between January 2004 and June 2026, 8,961 adverse event reports received by FDA list mesalamine, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (18,141) are left out of every figure here.

In the 12 months to June 2026, 1,401 reports listed it, down 19% from 1,728 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 398 reports a year and 0% of the 20,646,523 reports in the database, and 15.1% of the reports for the aminosalicylate class. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are drug ineffective (26.5%), off label use (15.7%) and colitis ulcerative (15.5%). A report can list several reactions, so shares add to more than 100%; 1,446 different terms appear across these reports. Drug ineffective is recorded in 26.5% of these reports, a larger share than in the median aminosalicylate drug (19.6%).

92% of the reports are marked serious by the reporter (86.5% across the class); 12.9% record death among the outcomes and 35.1% record hospitalisation, as reported. 47.3% of the reports came from other health professionals, and the largest patient age group is 18 to 44 (27.5%). 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

0112224Jul 2021: 36Aug 2021: 54Sep 2021: 48Oct 2021: 145Nov 2021: 87Dec 2021: 1962022Jan 2022: 91Feb 2022: 118Mar 2022: 112Apr 2022: 129May 2022: 148Jun 2022: 103Jul 2022: 86Aug 2022: 114Sep 2022: 92Oct 2022: 101Nov 2022: 125Dec 2022: 1172023Jan 2023: 103Feb 2023: 109Mar 2023: 125Apr 2023: 114May 2023: 172Jun 2023: 135Jul 2023: 195Aug 2023: 224Sep 2023: 110Oct 2023: 110Nov 2023: 80Dec 2023: 1032024Jan 2024: 105Feb 2024: 114Mar 2024: 124Apr 2024: 156May 2024: 142Jun 2024: 168Jul 2024: 156Aug 2024: 142Sep 2024: 142Oct 2024: 152Nov 2024: 117Dec 2024: 1222025Jan 2025: 189Feb 2025: 135Mar 2025: 162Apr 2025: 157May 2025: 95Jun 2025: 159Jul 2025: 137Aug 2025: 87Sep 2025: 140Oct 2025: 127Nov 2025: 136Dec 2025: 1152026Jan 2026: 100Feb 2026: 88Mar 2026: 144Apr 2026: 135May 2026: 82Jun 2026: 110

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

08201,6402004: 3020042005: 312006: 372007: 2820072008: 382009: 392010: 7720102011: 1252012: 1242013: 2920132014: 252015: 232016: 6220162017: 862018: 1402019: 16220192020: 2922021: 7592022: 1,33620222023: 1,5802024: 1,6402025: 1,63920252026: 659

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Mesalamine reports recording the termmedian drug in aminosalicylate

  1. Drug ineffectivethe medicine did not work as expected26.5%2,376
  2. Off label useused for a purpose or in a way not on the label15.7%1,404
  3. Pyrexiafever10.8%967
  4. Condition aggravatedthe condition being treated got worse10.8%965
  5. Weight decreasedweight loss10.3%925
  6. Painpain, site not specified9.9%884
  7. Headachehead pain9.6%857
  8. Diarrhoealoose or frequent stools8.7%779
  9. Fatiguetiredness8.3%742
  10. Nauseafeeling sick8.2%737
  11. Haematocheziablood in the stool8.2%732
  12. Abdominal painstomach or belly pain7.8%697
  13. Macular degenerationa disease of the central retina6.5%586
  14. Hypertensionhigh blood pressure6.3%561
  15. Rashskin rash6.2%552
  16. Malaisegeneral feeling of being unwell6%540
  17. Abdominal discomfortstomach discomfort5.8%520
  18. Depressionlow mood5.7%515
  19. Infusion related reactiona reaction during or soon after an infusion5.6%501
  20. Arthritis5.5%495
  21. Asthmaasthma5.4%480
  22. Product use in unapproved indicationused for a purpose not on the label5.2%465
  23. Arthralgiajoint pain5%448
  24. Weight increasedweight gain5%446
  25. Colitisinflamed bowel4.9%441

Top 30 of 1,446 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 7 drugs in the aminosalicylate 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

Death12.9%1,152
Life-threatening8.1%727
Hospitalisation (initial or prolonged)35.1%3,144
Disability7.3%653
Congenital anomaly3.8%337
Other serious77.3%6,923
Not serious8%720

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 59,220 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 20.4%33
2 to 112%175
12 to 173.9%350
18 to 4427.5%2,466
45 to 6415.8%1,413
65 to 748.1%722
75 and over6.2%555
Age not given36.2%3,247

Patient sex

Female51.1%4,575
Male33.7%3,017
Not given15.3%1,369

Who reported

Physician25.6%2,297
Pharmacist2%178
Other health professional47.3%4,240
Lawyer0%2
Consumer or non-health professional23.6%2,119
Not given1.4%125

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 23.4% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Colitis ulcerative2,66829.8%
Crohn's disease1,13212.6%
Colitis3093.4%
Inflammatory bowel disease1361.5%
Crohn's disease1321.5%
Colitis microscopic700.8%

The indication field is filled in by the reporter and is often blank; shares are of all 8,961 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Mesalamine reports
Prednisone2,70330.2%
Infliximab2,01122.4%
Azathioprine1,81220.2%
Humira1,73119.3%
Adalimumab1,63418.2%
Budesonide1,62718.2%
Acetaminophen1,59717.8%
Methotrexate1,45316.2%
Ergocalciferol1,30914.6%
Pregabalin1,18713.2%

Other products listed in reports where Mesalamine 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

MeasureMesalamineAminosalicylateAll reports
Reports as suspect product8,96159,22020,646,523
Share of that pool—15.1%0%
Reports, latest 12 months1,401—1,332,454
Marked serious92%86.5%57.4%
Death recorded among outcomes, per 1,000 reports12911391
Hospitalisation recorded, per 1,000 reports351289213
Consumer-filed share23.6%24.3%45.8%
Top term, share of reportsDrug ineffective 26.5%median 19.6%6.3%

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 aminosalicylate class

DrugName typeReportsLatest 12 monthsMarked serious
Sulfasalazinegeneric40,7412,02089.9%
Lialdabrand3,74916556.4%
Pentasabrand3,08214180.1%
Azulfidinebrand1,3329168.5%
Aprisobrand836242%
Azulfidine En-Tabsbrand5191497.5%

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 Mesalamine reports

How many adverse event reports has FDA received for Mesalamine?

8,961 reports list Mesalamine as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 1,401 of them arrived in the latest 12 months. Another 18,141 list it only as a concomitant medication.

What reactions are recorded in Mesalamine reports?

drug ineffective (26.5%), off label use (15.7%), colitis ulcerative (15.5%), pyrexia (10.8%) and condition aggravated (10.8%). 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 Mesalamine was responsible.

How serious are the reports?

92% are marked serious by the reporter. Among the outcomes recorded, 12.9% of reports include death and 35.1% 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 (47.3%), physician (25.6%) and consumer or non-health professional (23.6%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Mesalamine rising?

1,401 reports in the 12 months to June 2026, down 19% from 1,728 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 Mesalamine 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 Mesalamine?

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 Mesalamine as a suspect or interacting product; reports listing it only as a concomitant medication (18,141) 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.