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Drug side effects

tofacitinib Side Effects

The reactions most often reported to the FDA for tofacitinib (also sold as Xeljanz), with demographics, serious outcomes, and reporting trends.

Data updated 2026-05-15

181,998
FAERS reports

Data from the FDA Adverse Event Reporting System (FAERS), 2008 to 2025. A FAERS report records a temporal association, not proof of cause. See our methodology for how figures are compiled and de-duplicated.

The most commonly reported side effects of tofacitinib come from 181,998 reports to the FDA, broken down here by frequency, patient demographics, and serious outcomes.

This page analyzes 181,998 reports to the FDA Adverse Event Reporting System (FAERS) for tofacitinib (Xeljanz): the reactions reported most often, who reported them, serious outcomes such as hospitalization, and year-over-year trends. A FAERS report does not prove the drug caused the effect, and report volume tracks how widely a drug is used, not how likely an effect is for any one person. Educational information, not medical advice.

Total Reports

181,998

Reports Mentioning Death

8,655

4.8% of reports — not proof the medicine caused the death

Hospitalizations

24,557

13.5% of reports

Top Indication

Rheumatoid Arthritis

Most Reported Adverse Reactions

PAIN
25,737
ARTHRALGIA
19,670
CONDITION AGGRAVATED
19,467
RHEUMATOID ARTHRITIS
18,797
FATIGUE
16,595
JOINT SWELLING
14,455
HEADACHE
13,405
RASH
11,912
MALAISE
10,489
PAIN IN EXTREMITY
10,277
ABDOMINAL DISCOMFORT
10,168
NAUSEA
9,949
DIARRHOEA
9,695
PERIPHERAL SWELLING
9,668
ALOPECIA
9,255
MUSCULOSKELETAL STIFFNESS
9,233
SYNOVITIS
9,206

Who Reports Side Effects

Gender Distribution

Female 138,558 (80%)
Male 33,777 (20%)
Unknown 277

Age Distribution

0-17 1,620 (1%)
18-44 23,187 (16%)
45-64 69,765 (47%)
65-74 35,158 (24%)
75+ 17,340 (12%)

Reporting Trend by Year

2008 2025

Reactions in Death Reports

Top reactions reported in 8,655 reports where death was an outcome. These are voluntarily reported and do not establish causation.

Reaction Reports
DEATH 3,491
JOINT SWELLING 1,969
RHEUMATOID ARTHRITIS 1,950
PAIN 1,933
RASH 1,899
INFUSION RELATED REACTION 1,889
FATIGUE 1,860
SYNOVITIS 1,848
SYSTEMIC LUPUS ERYTHEMATOSUS 1,844
GLOSSODYNIA 1,840
TYPE 2 DIABETES MELLITUS 1,836
WOUND 1,826
HEPATIC ENZYME INCREASED 1,796
HYPERTENSION 1,796
GENERAL PHYSICAL HEALTH DETERIORATION 1,768
HAND DEFORMITY 1,768
PSORIATIC ARTHROPATHY 1,732
HYPOAESTHESIA 1,729
SWELLING 1,719

Reactions in Hospitalization Reports

Top reactions in 24,557 reports where hospitalization was an outcome.

Reaction Reports
PAIN 5,294
RHEUMATOID ARTHRITIS 4,484
CONDITION AGGRAVATED 4,373
ARTHRALGIA 4,344
FATIGUE 4,196
RASH 3,865
JOINT SWELLING 3,732
ARTHROPATHY 3,429
SYNOVITIS 3,310
PERIPHERAL SWELLING 3,152
PNEUMONIA 3,053
MALAISE 3,046
DRUG HYPERSENSITIVITY 3,037
HYPERSENSITIVITY 3,027
ABDOMINAL DISCOMFORT 2,985
INFECTION 2,974
HEADACHE 2,923

Compare tofacitinib vs abatacept →

What the FAERS Data Reveals About tofacitinib Side Effects

The FDA Adverse Event Reporting System (FAERS) contains 181,998 voluntary reports linked to tofacitinib and its brand equivalents (Xeljanz), spanning 2008 through 2025. Of those, 8,655 (4.8%) listed death as an outcome and 24,557 (13.5%) involved hospitalization. The most common indication reported alongside adverse events was Rheumatoid Arthritis.

Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 80% were female and 20% male; age distribution skews toward 45-64, with 69,765 reports in that bracket. The single most reported reaction is pain with 25,737 submissions, followed by arthralgia and condition aggravated.

How to read these numbers

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.