Azulfidine (sulfasalazine) adverse event reports that FDA received

Name: Reaction terms in FDA adverse event reports that name Azulfidine
Creator: Reported Reactions
License: https://creativecommons.org/publicdomain/zero/1.0/

Name type: Brand name
Generic name: Sulfasalazine
Class: Aminosalicylate

What a report is

A report is not proof that the drug was the cause of the event.

FDA says:

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product.
Source: openFDA, Drug Adverse Event Overview, section "Responsible use of the data". The site read the page on 2 Oct 2026. The data have the reports that FDA received through 30 Jun 2026.

FDA also says:

There is no certainty that the reported event (adverse event or medication error) was actually due to the product. FDA does not require that a causal relationship between a product and event be proven, and reports do not always contain enough detail to properly evaluate an event. The information in these reports has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.
Source: openFDA, Response of the drug event API (meta.disclaimer). The site read the page on 2 Oct 2026.

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

Drug reports received through 30 Jun 2026. Device reports have a separate cutoff, 30 Sep 2026. Why a report count is not a rate.

Reports on file

From January 2004 to June 2026, FDA received 1,332 adverse event reports that name Azulfidine. In these reports the drug is a suspect or interacting product.

In the same period, 2,076 further reports name it only as a concomitant medicine. The counts on this page do not include these reports.

FDA received 91 reports in the 12 months to June 2026 and 107 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Of the 1,332,454 drug reports that FDA received in the 12 months to June 2026, 91 (under 0.1%) name Azulfidine. Reports from consumers or other non-health professionals were 19.4% of the reports that name Azulfidine and 45.8% of all drug reports.

The number of people who use the product is not in the data. A count is not a rate. A count of reports is not a count of events or of patients, because one event can have more than one report.

There are many instances of duplicative reports and some reports do not contain all the necessary information.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

Suspect product

FDA records each drug in a report as suspect, concomitant or interacting. This page counts the reports in which Azulfidine is suspect or interacting. FDA says:

Any number of the drugs may be marked as suspect if thought to be responsible for one or more of the reactions, but that information is not validated.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

Data version

openFDA FAERS release of 29 Oct 2026. Reports received through 30 Jun 2026.

Since the last update

FDA says:

Many factors can influence whether or not an event will be reported, such as the time a product has been marketed and publicity about an event.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

The information in these reports cannot be used to estimate the incidence (occurrence rates) of the events reported.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

The latest update of the FDA data, recorded on 28 Oct 2026, changed no count of this page.

In April to June 2026, FDA received 26 reports that name Azulfidine.
In January to March 2026, FDA received 18.
In April to June 2025, FDA received 30.

April to June 2026 is the latest closed quarter in the data. A closed quarter is a quarter for which the FDA files have most of the reports.

All updates Feed of updates (RSS)

Reaction lookup

These are the reaction terms that the reports record, with the number of reports for each term. Type a term or a plain word to find its count.

What this list leaves out

The table lists the 253 reaction terms that 5 or more reports record. A term with fewer than 5 reports is not in the table.

The site keeps reaction terms for all 1,332 reports.

The site keeps a term for a year only if two or more reports of that year record it.

So a count in the table can be lower than the count of FDA.

Find a reaction term

The table shows the first 50 of 253 terms.

Reaction terms in the reports that name Azulfidine, most reports first
Reaction term (MedDRA) and plain meaning	Reports	Share of the 1,332 reports
Drug ineffectivethe medicine did not work as expected	261	19.6%
Drug hypersensitivityan allergic-type reaction (the term names a medicine)	246	18.5%
Diarrhoealoose or frequent stools	157	11.8%
Rashskin rash	151	11.3%
Headachehead pain	142	10.7%
Pyrexiafever	142	10.7%
Arthralgiajoint pain	136	10.2%
Dizzinesslight-headedness or unsteadiness	135	10.1%
Painpain, site not specified	127	9.5%
Astheniaweakness or lack of energy	126	9.5%
Decreased appetitereduced appetite	126	9.5%
Night sweatssweating at night	126	9.5%
Abdominal pain upperupper stomach pain	125	9.4%
Joint range of motion decreasedreduced movement of a joint	125	9.4%
Off label useused for a purpose or in a way not on the label	124	9.3%
Frequent bowel movements	123	9.2%
Contraindicated product administered	122	9.2%
Bursitis	121	9.1%
Joint swellinga swollen joint	120	9%
Muscle spasmsmuscle cramps	120	9%
Lung disordera lung problem, type not specified	119	8.9%
Psoriatic arthropathy	119	8.9%
Hepatic enzyme increasedraised liver enzymes	118	8.9%
Rheumatoid arthritisrheumatoid arthritis, an inflammatory joint disease	118	8.9%
Depressionlow mood	117	8.8%
Peripheral swellingswelling of the arms or legs	117	8.8%
Liver disorder	115	8.6%
Musculoskeletal painpain in muscles or bones	115	8.6%
Abdominal discomfortstomach discomfort	113	8.5%
Feeling hot	113	8.5%
Irritable bowel syndrome	113	8.5%
Impaired healingslow healing	112	8.4%
Dry mouth	111	8.3%
C-reactive protein abnormal	110	8.3%
Paraesthesiatingling or pins and needles	109	8.2%
Exposure during pregnancythe medicine was taken during pregnancy	106	8%
Infusion related reactiona reaction during or soon after an infusion	106	8%
Anti-cyclic citrullinated peptide antibody positive	105	7.9%
Folliculitis	105	7.9%
Blood cholesterol increasedraised cholesterol	104	7.8%
Contusiona bruise	104	7.8%
Pericarditisinflammation of the sac around the heart	104	7.8%
Dislocation of vertebra	103	7.7%
Insomniadifficulty sleeping	103	7.7%
Glossodynia	101	7.6%
General physical health deteriorationgeneral decline in health	100	7.5%
Hypersensitivityan allergic-type reaction	100	7.5%
Osteoporosisthinning of the bones	100	7.5%
Condition aggravatedthe condition being treated got worse	99	7.4%
Retinitis	99	7.4%

Download all 253 terms of Azulfidine (CSV)

The counts add to more than 1,332 reports, because one report can record more than one term. FDA says:

No individual drug is connected to any individual reaction. When a report lists multiple drugs and multiple reactions, there is no way to conclude from the data therein that a given drug is responsible for a given reaction.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

The CSV file has the same rows and the same limits. Its last row is a note that says so.

MedDRA term

The person who codes a report selects the preferred term that agrees best with the description of the reporter. The words under a term are the plain meaning that this site gives.

Not the label

The FDA-approved label of a product lists its adverse reactions. See the official pages at the end of this page.

Same ingredient, other names

Reporters write a brand name or a generic name. Each name has its own page and its own count.

Names of Sulfasalazine with a page, in the order generic names, brand names, names as reported
Name	Name type	Reports
Sulfasalazine	Generic name	40,741
Azulfidine (this page)	Brand name	1,332
Azulfidine En-Tabs	Brand name	519

Sum of the separately reported names: 42,592. A report that names two of these names is in the sum two times. The sum is not the number of reports for the ingredient.

FDA says:

Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

Importantly, the AEMS data by themselves are not an indicator of the safety profile of the drug or biologic.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

Outcomes by year

The table gives the outcomes that the reporters gave, in the terms of FDA.

Outcomes in the reports that name Azulfidine, by the year of the openFDA file that holds the report

The table continues to the right.

Year of the openFDA file	Reports	Serious	Death	Life-threatening	Hospitalization (initial or prolonged)	Disability or Permanent Damage	Congenital Anomaly/Birth Defect	Other Serious (Important Medical Events)	Not serious
2004	28	25	0	1	15	0	0	10	3
2005	15	14	2	1	9	0	0	6	1
2006	21	21	2	6	13	2	0	14	0
2007	18	17	0	1	5	1	0	14	1
2008	23	18	1	2	12	0	0	7	5
2009	61	54	7	4	34	3	0	37	7
2010	129	123	5	11	43	0	0	104	6
2011	106	104	13	7	54	0	0	75	2
2012	72	63	4	6	29	0	0	47	9
2013	35	19	1	2	5	0	0	16	16
2014	54	28	1	4	6	0	0	22	26
2015	46	19	0	0	4	0	0	16	27
2016	38	20	0	1	6	0	0	15	18
2017	81	19	0	0	5	1	0	16	62
2018	136	36	1	0	13	0	0	28	100
2019	61	19	0	0	5	0	0	16	42
2020	30	12	1	0	4	0	0	10	18
2021	19	14	0	1	5	0	0	12	5
2022	64	25	0	1	6	1	0	20	39
2023	53	30	4	13	19	12	0	25	23
2024	52	50	29	37	44	38	22	48	2
2025	103	101	77	84	90	85	32	95	2
2026	87	82	74	74	76	74	61	80	5

An outcome in a report is not proof that the drug was the cause. The reporter gives the outcome, and FDA does not verify it. FDA says:

The information in these reports has not been scientifically or otherwise verified as to a cause and effect relationship and cannot be used to estimate the incidence of these events.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

The six headings with the names of FDA are the outcome terms of FDA. A report can have more than one outcome. The columns Serious and Not serious are the two values of the openFDA field serious. For the value serious, openFDA gives this description:

The adverse event resulted in death, a life threatening condition, hospitalization, disability, congenital anomaly, or other serious condition
Source: openFDA, Drug adverse event fields (YAML reference). The site read the page on 2 Oct 2026.

The year is the year of the openFDA file that holds the latest version of the report. It is not always the year in which FDA first received the report. The chart of the next section uses the year of first receipt. The latest year is not complete.

Reports by year and month

Reports that name Azulfidine, by the year in which FDA received them

The column of 2026 has an outline, because the year is not complete. It has the reports that FDA received through June 2026 only.

Show the figures of the chart as a table

Reports that name Azulfidine, by the year in which FDA received them
Year	Reports
2004	24
2005	17
2006	21
2007	16
2008	18
2009	53
2010	133
2011	119
2012	80
2013	34
2014	55
2015	53
2016	32
2017	94
2018	133
2019	62
2020	29
2021	19
2022	64
2023	56
2024	73
2025	103
2026	44

Reports that name Azulfidine, by month, five years to June 2026

FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

Why a count moves

A count moves for many reasons. The guide gives FDA's words about them.

Patients and reporters

Age of the patient in the reports that name Azulfidine
Age	Reports	Share
Under 2	0	0%
2 to 11	2	0.2%
12 to 17	7	0.5%
18 to 44	278	20.9%
45 to 64	336	25.2%
65 to 74	167	12.5%
75 and over	120	9%
Age not given	422	31.7%

Sex of the patient in the reports that name Azulfidine
Sex	Reports	Share
Female	867	65.1%
Male	269	20.2%
Unknown or not given	196	14.7%

Type of reporter in the reports that name Azulfidine
Reporter	Reports	Share
Physician	560	42%
Pharmacist	107	8%
Other health professional	377	28.3%
Lawyer	4	0.3%
Consumer or non-health professional	258	19.4%
Not given	26	2%

Age and sex are as the report gives them. The reporter is the primary source in the report. 43.5% of the reports give the United States as the country.

Reason for use

Reason for use (indication) that the reports of Azulfidine record
Indication as recorded (MedDRA)	Reports	Share
Rheumatoid arthritis	461	34.6%
Colitis ulcerative	48	3.6%
Arthritis	8	0.6%
Crohn's disease	8	0.6%
Psoriatic arthropathy	8	0.6%
Crohn's disease	7	0.5%

The reporter fills in the indication, and the field is often empty. Each share is of all 1,332 reports.

Pages near this one

Sulfasalazine same ingredient
Azulfidine En-Tabs same ingredient
Apriso same class
Canasa same class
Lialda same class
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Aztreonam next in the A to Z list
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These links are for navigation. No count selected them. The class page lists each drug of the class.

Official pages

DailyMed labels for AzulfidineThe labels (prescribing information) that have this name, at the National Library of Medicine.
MedWatch Online Voluntary Reporting FormThe online form of FDA for a voluntary report.
MedWatch: The FDA Safety Information and Adverse Event Reporting ProgramThe page of the FDA program that receives reports about drugs and devices.
FDA Adverse Event Monitoring System (AEMS) Public DashboardThe public dashboard of FDA for adverse event reports on drugs and biologics.

The site checked these addresses on 2 Oct 2026. The links open in a new tab.

Cite this page

Reported Reactions. Azulfidine: adverse event reports that FDA received. https://reportedreactions.com/drug/azulfidine/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of 29 Oct 2026. Reports received through 30 Jun 2026.

Where the data come from

The counts come from the openFDA Drug Adverse Event (FAERS) bulk files, release of 29 Oct 2026. The files have the reports that FDA received through 30 Jun 2026. A drug name is the name on the report. The site matches it to a brand name or a generic name of the National Drug Code Directory of 2 Nov 2026. A class is the pharmacologic class (EPC) of the FDA label.

A report is in the count when it names Azulfidine as a suspect or interacting product. The 2,076 reports that name it only as a concomitant medicine are not in the count. The site does not publish a report narrative, a lot number, a detail of a patient or the identity of a reporter. The record of FDA is the authority. See how the site counts reports, the data sources and the corrections page.

Questions

Do these reports show that Azulfidine was responsible for the reactions?

No. FDA says:

For any given report, there is no certainty that a suspected drug caused the event.
Source: FDA, FDA Adverse Event Monitoring System (AEMS) Public Dashboard. Content current as of 11 Mar 2026. The site read the page on 2 Oct 2026.

A reaction can relate to the condition that the drug treats, to other medicines, or to something else.

Is this the list of reactions on the label of Azulfidine?

No. It is a count of what people reported to FDA: 1,332 reports from January 2004 to June 2026. The FDA-approved label of a product lists its adverse reactions. The official pages at the end of this page link to the labels.

Who sent these reports?

Physician (42%), other health professional (28.3%) and consumer or non-health professional (19.4%). These are the types of reporter for the reports that name this drug.

If a manufacturer receives an adverse event report, it is normally required to send the report to FDA.
Source: openFDA, Drug Adverse Event Overview. The site read the page on 2 Oct 2026.

How does a person report an adverse event?

FDA runs MedWatch, a program that takes voluntary reports from health professionals, patients and consumers. The guide on how to report has the links.

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