Reported Reactions

Adverse event reports that FDA received

  • Search
  • Watch list

Janus kinase inhibitor adverse event reports that FDA received for the drugs of this class

Kind of class
Pharmacologic class (FDA Established Pharmacologic Class)
Drug pages
11

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 . The data have the reports that FDA received through .

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 .

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 .

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

Reports on file

Janus kinase inhibitor is a pharmacologic class: an FDA Established Pharmacologic Class. The class has 11 drug pages on this site.

From February 2010 to June 2026, FDA received 323,323 adverse event reports that name a drug of the class. In these reports the drug is a suspect or interacting product. A report that names two drugs of the class counts one time for each.

FDA received 28,142 reports in the 12 months to June 2026 and 34,689 in the 12 months before. FDA releases FAERS data every quarter, so the newest months are not complete. They grow in later releases.

The number of people who use the product is not in the data. A count is not a rate.

Pharmacologic class

The Established Pharmacologic Class (EPC) of FDA is the class on the label of a drug. The site puts a drug in the class that its reports have most often.

Data version

openFDA FAERS release of 1 Oct 2026. Reports received through 30 Jun 2026.

Drugs of the class

The rows are in order of name. A brand name and its generic name are separate rows, because reporters name them separately.

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 .

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 . The site read the page on .

Drug pages of the class Janus kinase inhibitor, in order of name
DrugName typeReportsReports, 12 months to June 2026
BaricitinibGeneric name2,365218
CibinqoAbrocitinibBrand name3,149503
JakafiRuxolitinibBrand name55,3914,584
OlumiantBaricitinibBrand name6,205396
OpzeluraRuxolitinibBrand name3,285660
RinvoqUpadacitinibBrand name73,18714,085
RuxolitinibGeneric name8,8151,361
TofacitinibGeneric name4,874860
Tofacitinib citrateGeneric name5,775628
UpadacitinibGeneric name4,1951,276
XeljanzTofacitinibBrand name156,0823,571

Reaction lookup

These are the reaction terms that the reports of the class record. Type a term or a plain word to find its count.

What this list leaves out

The table lists the 3,544 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 323,246 of the 323,323 reports (99.9%).

The reports of the other years are not in the counts.

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

The table shows the first 50 of 3,544 terms.

Reaction terms in the reports that name a janus kinase inhibitor drug, most reports first
Reaction term (MedDRA) and plain meaningReportsShare of the 323,323 reports
Drug ineffectivethe medicine did not work as expected40,51812.5%
Painpain, site not specified31,4959.7%
Off label useused for a purpose or in a way not on the label31,1419.6%
Fatiguetiredness24,8697.7%
Arthralgiajoint pain24,0097.4%
Condition aggravatedthe condition being treated got worse21,6916.7%
Rheumatoid arthritisrheumatoid arthritis, an inflammatory joint disease18,5315.7%
Headachehead pain17,6195.4%
Joint swellinga swollen joint14,9524.6%
Rashskin rash14,0934.4%
Pain in extremitypain in an arm or leg14,0004.3%
Diarrhoealoose or frequent stools13,8444.3%
Malaisegeneral feeling of being unwell13,6504.2%
Nauseafeeling sick13,5764.2%
Peripheral swellingswelling of the arms or legs11,9883.7%
Nasopharyngitisa cold11,8383.7%
Abdominal discomfortstomach discomfort11,7113.6%
Deaththe patient died; cause not stated by this term11,5063.6%
Alopeciahair loss10,9453.4%
Musculoskeletal stiffnessstiffness in muscles or joints10,8633.4%
Swelling10,8443.4%
Pneumonialung infection10,6403.3%
Arthropathy10,4293.2%
Drug intolerancethe medicine was not tolerated10,3793.2%
Dyspnoeashortness of breath10,1383.1%
Weight increasedweight gain10,0463.1%
Synovitis9,9603.1%
Infectionan infection, type not specified9,9403.1%
Hepatic enzyme increasedraised liver enzymes9,5573%
Covid-19COVID-19 infection9,4432.9%
Dizzinesslight-headedness or unsteadiness9,3262.9%
Hypersensitivityan allergic-type reaction9,1472.8%
Pyrexiafever8,8972.8%
Systemic lupus erythematosuslupus, an autoimmune disease8,6342.7%
Vomitingbeing sick8,4322.6%
Falla fall8,4252.6%
Product dose omission issuea dose was missed8,4012.6%
Hypertensionhigh blood pressure8,3662.6%
Blood cholesterol increasedraised cholesterol8,2852.6%
Pruritusitching8,1712.5%
Sinusitissinus infection8,1292.5%
Contraindicated product administered8,1062.5%
Hand deformity8,1022.5%
Astheniaweakness or lack of energy7,9772.5%
Wound7,8822.4%
Glossodynia7,8062.4%
Pemphigus7,6652.4%
Therapeutic product effect decreased7,6462.4%
Infusion related reactiona reaction during or soon after an infusion7,5882.3%
Treatment failurethe treatment did not work7,4952.3%

Download all 3,544 terms of the class (CSV)

The counts add to more than 323,323 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 .

Reports by month

Reports that name a janus kinase inhibitor drug, by month, five years to June 2026
05,00010,00020222023202420252026

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

Outcomes, patients and reporters

Outcomes in the reports of the class Janus kinase inhibitor
OutcomeReportsShareShare as a bar
Death24,3287.5%
Life-threatening10,8353.4%
Hospitalization (initial or prolonged)61,37819%
Disability or Permanent Damage11,8643.7%
Congenital Anomaly/Birth Defect3,7771.2%
Other Serious (Important Medical Events)130,78640.5%
Not serious151,63646.9%

An outcome in a report is not proof that a drug was the cause. The reporter gives the outcome, and FDA does not verify it. A report can have more than one outcome. 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 .

Age of the patient in the reports of the class Janus kinase inhibitor
AgeReportsShareShare as a bar
Under 22040.1%
2 to 111,3300.4%
12 to 172,0840.6%
18 to 4435,06210.8%
45 to 6491,80828.4%
65 to 7450,42015.6%
75 and over28,7078.9%
Age not given113,70835.2%
Type of reporter in the reports of the class Janus kinase inhibitor
ReporterReportsShareShare as a bar
Physician51,38615.9%
Pharmacist8,9442.8%
Other health professional90,87828.1%
Lawyer2430.1%
Consumer or non-health professional168,54452.1%
Not given3,3281%

Official pages

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

Cite this page

Reported Reactions. Janus kinase inhibitor: adverse event reports that FDA received. https://reportedreactions.com/class/janus-kinase-inhibitor/ Source: U.S. Food and Drug Administration, openFDA Drug Adverse Event (FAERS) files, release of . Reports received through .

Where the data come from

The counts come from the openFDA Drug Adverse Event (FAERS) bulk files, release of 1 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 Oct 2026. A class is the pharmacologic class (EPC) of the FDA label.

The class of a drug is the Established Pharmacologic Class that openFDA attaches to its reports most often. When the reports have none, it is the class in the NDC Directory. 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

Which drugs are in the Janus kinase inhibitor class on this site?

Baricitinib, Cibinqo, Jakafi, Olumiant, Opzelura, Rinvoq and 5 more, in order of name. The class of a drug comes from the pharmacologic class (EPC) on its FDA label.

Can the table of drugs rank the drugs?

No. FDA says:

Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product.

Source: openFDA, Drug Adverse Event Overview. The site read the page on .

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 .

Drugs also differ in the conditions that they treat and in their time on the market.

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.