Ruxolitinib side effects: what 71,064 FDA adverse event reports show

Ruxolitinib · Jakafi, Jakafi Xr · 1,205 reaction terms · 219,752 drug–reaction co-reports · data 2026-09-14

Drug class

Kinase Inhibitor, Janus Kinase Inhibitor

FDA label (Established Pharmacologic Class) · compare the class

Brand names

Jakafi, Jakafi Xr

openFDA label

Who reports

71,064 reports · 49% serious · 9,813 with death outcome · 48% female

openFDA FAERS counts, all years, deduplication not applied

Used for

JAKAFI/JAKAFI XR is a kinase inhibitor indicated for treatment of: intermediate or high-risk myelofibrosis, including primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis in adults. ( 1.1 ) polycythemia vera in adults who have had an inadequate response to or are intolerant of hydroxyurea.

FDA label, Indications and Usage

What it is

Ruxolitinib phosphate is a kinase inhibitor with the chemical name ( R )-3-(4-(7 H -pyrrolo[2,3- d ]pyrimidin-4-yl)-1 H -pyrazol-1-yl)-3-cyclopentylpropanenitrile phosphate and a molecular weight of 404.36.

FDA label, Description section

Boxed warning

None in the current label

How to read this page. FAERS is a spontaneous-reporting system: counts are not incidence rates and a signal is not proof of causation. Each reaction below is run through an automated screen — is the term in the FDA label (known), in the indications (the disease being treated), an administrative/coding term, or none of these (unlabeled)? That screen is mechanical text matching, not a causality assessment. The 30 hand-written Bradford Hill assessments are on the causality assessment page. Not medical advice.

Causality screen of the 40 strongest signals

Labeled adverse reaction 1Labeled (related wording) 4Likely indication confounding 7Reporting / coding artifact 1Lab value / disease marker 12Not in label — unassessed 15

What the badges mean

Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
Likely indication confounding The term appears in the label's indications: reports probably describe the disease being treated (or its progression), not a drug effect. Classic confounding by indication.
Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.

Strongest disproportionality signals

Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only (and, for the 300 most-reported drugs, adjusted for age band), and flags pairs whose reports are unusually skewed by sex or come mostly from consumers. Each row also shows the PRR against the other drugs of the same FDA class, which removes most confounding by the condition being treated, and a calibrated p-value: on validation, known non-causes average an ROR of about 2, so significance is judged against that empirical null (✓ = p < 0.05 after calibration). 1,165 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.

Show: hide coding/lab/outcome terms hide indication terms unlabeled only hide PRR-only

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Disease propensity	47	4,534.9 1,411.5–14,569.6ROR 4,537.9 · calibrated p 3e-16 ✓	245.8 EB05 192.3 · IC025 +5.7 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	100% clinician	not reported in cached trials
Blood erythropoietin abnormal	36	521.0 301.6–900.0ROR 521.3 · calibrated p 1e-12 ✓	170.0 EB05 128.3 · IC025 +5.2 3/3 methods agree vs other Kinase Inhibitors: only this drug	Lab value / disease marker	100% consumer	not reported in cached trials
Aquagenic pruritus	48	463.1 293.5–730.8ROR 463.4 · calibrated p 2e-12 ✓	167.0 EB05 131.0 · IC025 +5.5 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=27 · 100% consumer	not reported in cached trials
Bronchiolitis obliterans syndrome	61	166.6 121.6–228.2ROR 166.7 · calibrated p 4e-9 ✓	102.8 EB05 82.9 · IC025 +5.4 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=61 · 100% clinician	not reported in cached trials
Chronic graft versus host disease in lung	56	146.0 105.9–201.3ROR 146.1 · calibrated p 1e-8 ✓	94.3 EB05 75.4 · IC025 +5.3 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=56	not reported in cached trials
Myelofibrosis	931	130.9 121.2–141.4ROR 132.7 · calibrated p 1e-8 ✓	90.3 EB05 85.5 · IC025 +6.3 3/3 methods agree vs other Kinase Inhibitors: PRR 11,243.1 (4,669.1–27,073.5)	Likely indication confounding term in indications; also in warnings	serious n=915	not reported in cached trials
Primary myelofibrosis	92	120.5 94.5–153.7ROR 120.7 · calibrated p 4e-8 ✓	83.9 EB05 70.5 · IC025 +5.5 3/3 methods agree vs other Kinase Inhibitors: only this drug	Likely indication confounding term in indications; also in warnings	serious n=92	not reported in cached trials
Haematocrit abnormal	318	102.0 89.8–115.9ROR 102.5 · calibrated p 1e-7 ✓	75.4 EB05 68.7 · IC025 +5.9 3/3 methods agree vs other Kinase Inhibitors: PRR 1,129.5 (693.5–1,839.6)	Lab value / disease marker	serious n=84 · 86% consumer	not reported in cached trials
Chronic graft versus host disease in eye	40	74.7 52.8–105.7ROR 74.7 · calibrated p 2e-6 ✓	58.0 EB05 44.4 · IC025 +4.6 3/3 methods agree vs other Kinase Inhibitors: only this drug	Likely indication confounding term in indications; also in warnings	serious n=40 · 100% clinician	not reported in cached trials
Chronic graft versus host disease oral	42	62.3 44.7–87.0ROR 62.4 · calibrated p 6e-6 ✓	50.4 EB05 38.8 · IC025 +4.5 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=42 · 100% clinician	not reported in cached trials
Myeloproliferative neoplasm	112	60.7 49.5–74.4ROR 60.8 · calibrated p 5e-6 ✓	50.0 EB05 42.7 · IC025 +5.1 3/3 methods agree vs other Kinase Inhibitors: only this drug	Labeled adverse reaction exact term	serious n=111	not reported in cached trials
Blast cells present	77	56.3 44.1–71.8ROR 56.3 · calibrated p 8e-6 ✓	46.8 EB05 38.6 · IC025 +4.8 3/3 methods agree vs other Kinase Inhibitors: only this drug	Lab value / disease marker	serious n=63 · 71% consumer	not reported in cached trials
Polycythaemia vera	129	55.5 46.0–67.0ROR 55.6 · calibrated p 8e-6 ✓	46.4 EB05 40.1 · IC025 +5.0 3/3 methods agree vs other Kinase Inhibitors: only this drug	Likely indication confounding term in indications; also in warnings	serious n=127	not reported in cached trials
Graft versus host disease in liver	109	53.1 43.3–65.1ROR 53.2 · calibrated p 1e-5 ✓	44.7 EB05 38.1 · IC025 +4.9 3/3 methods agree vs other Kinase Inhibitors: PRR 438.8 (255.8–752.7)	Not in label — unassessed	serious n=109	not reported in cached trials
Splenomegaly	1,764	52.2 49.6–54.8ROR 53.4 · calibrated p 9e-6 ✓	44.3 EB05 42.6 · IC025 +5.4 3/3 methods agree vs other Kinase Inhibitors: PRR 183.0 (166.8–200.8)	Not in label — unassessed	serious PRR 37.5	not reported in cached trials
Haematocrit increased	343	52.0 46.3–58.3ROR 52.2 · calibrated p 1e-5 ✓	44.1 EB05 40.3 · IC025 +5.2 3/3 methods agree vs other Kinase Inhibitors: PRR 2,958.7 (1,400.1–6,252.5)	Lab value / disease marker	serious n=93	not reported in cached trials
Graft versus host disease in eye	34	50.7 35.2–73.0ROR 50.8 · calibrated p 2e-5 ✓	42.4 EB05 31.7 · IC025 +4.2 3/3 methods agree vs other Kinase Inhibitors: only this drug	Likely indication confounding term in indications; also in warnings	serious n=33	not reported in cached trials
Chronic graft versus host disease in intestine	25	45.5 29.9–69.4ROR 45.5 · calibrated p 5e-5 ✓	38.4 EB05 27.4 · IC025 +3.8 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=25 · 100% clinician	not reported in cached trials
Graft versus host disease in lung	63	44.9 34.4–58.6ROR 45.0 · calibrated p 4e-5 ✓	38.6 EB05 31.2 · IC025 +4.5 3/3 methods agree vs other Kinase Inhibitors: PRR 345.8 (182.3–656.1)	Not in label — unassessed	serious n=63	not reported in cached trials
Platelet count abnormal	783	43.9 40.7–47.3ROR 44.3 · calibrated p 3e-5 ✓	38.2 EB05 36.0 · IC025 +5.1 3/3 methods agree vs other Kinase Inhibitors: PRR 146.8 (129.0–167.1)	Lab value / disease marker	serious n=321 · 80% consumer	not reported in cached trials
Blood lactate dehydrogenase abnormal	82	40.8 32.4–51.4ROR 40.8 · calibrated p 6e-5 ✓	35.6 EB05 29.6 · IC025 +4.5 3/3 methods agree vs other Kinase Inhibitors: only this drug	Lab value / disease marker	serious n=35 · 100% consumer	not reported in cached trials
Platelet count increased	1,536	39.1 37.1–41.3ROR 40.0 · calibrated p 5e-5 ✓	34.6 EB05 33.2 · IC025 +5.0 3/3 methods agree vs other Kinase Inhibitors: PRR 212.7 (191.4–236.4)	Lab value / disease marker	serious PRR 26.0	not reported in cached trials
Spleen disorder	194	37.8 32.6–43.9ROR 37.9 · calibrated p 8e-5 ✓	33.5 EB05 29.7 · IC025 +4.7 3/3 methods agree vs other Kinase Inhibitors: PRR 300.4 (213.0–423.6)	Not in label — unassessed	serious n=110 · 82% consumer	not reported in cached trials
Transformation to acute myeloid leukaemia	74	37.3 29.2–47.4ROR 37.3 · calibrated p 1e-4 ✓	32.9 EB05 27.0 · IC025 +4.4 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=74	not reported in cached trials
Graft versus host disease in gastrointestinal tract	223	34.4 29.9–39.5ROR 34.5 · calibrated p 1e-4 ✓	30.8 EB05 27.5 · IC025 +4.6 3/3 methods agree vs other Kinase Inhibitors: PRR 641.2 (410.0–1,002.8)	Labeled (related wording) related wording	serious n=223 · 91% clinician	not reported in cached trials
Mean cell volume abnormal	49	34.3 25.5–46.2ROR 34.4 · calibrated p 2e-4 ✓	30.5 EB05 24.0 · IC025 +4.1 3/3 methods agree vs other Kinase Inhibitors: only this drug	Lab value / disease marker	100% consumer	not reported in cached trials
Product availability issue	2,331	34.1 32.7–35.6ROR 35.2 · calibrated p 1e-4 ✓	30.6 EB05 29.6 · IC025 +4.9 3/3 methods agree vs other Kinase Inhibitors: PRR 1,058.3 (889.0–1,259.8)	Reporting / coding artifact	serious PRR 13.4 · ♀ 72% (drug 48%) · 86% consumer	not reported in cached trials
Red blood cell count abnormal	150	33.6 28.3–39.7ROR 33.6 · calibrated p 2e-4 ✓	30.1 EB05 26.2 · IC025 +4.5 3/3 methods agree vs other Kinase Inhibitors: PRR 65.2 (51.8–82.0)	Lab value / disease marker	serious n=73 · 83% consumer	not reported in cached trials
Iron overload	109	33.0 27.0–40.2ROR 33.0 · calibrated p 2e-4 ✓	29.6 EB05 25.2 · IC025 +4.4 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=98 · ♀ 14% (drug 48%)	not reported in cached trials
Chronic graft versus host disease in liver	36	32.7 23.1–46.1ROR 32.7 · calibrated p 2e-4 ✓	29.1 EB05 21.9 · IC025 +3.9 3/3 methods agree vs other Kinase Inhibitors: only this drug	Not in label — unassessed	serious n=36 · 100% clinician	not reported in cached trials
Chronic graft versus host disease in skin	91	32.6 26.3–40.5ROR 32.6 · calibrated p 2e-4 ✓	29.2 EB05 24.5 · IC025 +4.3 3/3 methods agree vs other Kinase Inhibitors: only this drug	Labeled (related wording) related wording	serious n=91 · 100% clinician	not reported in cached trials
Disease risk factor	37	30.5 21.7–42.8ROR 30.5 · calibrated p 3e-4 ✓	27.4 EB05 20.7 · IC025 +3.8 3/3 methods agree vs other Kinase Inhibitors: only this drug	Labeled (related wording) related wording	100% consumer	not reported in cached trials
Graft versus host disease in skin	202	29.7 25.7–34.3ROR 29.7 · calibrated p 3e-4 ✓	26.9 EB05 24.0 · IC025 +4.4 3/3 methods agree vs other Kinase Inhibitors: PRR 145.2 (112.6–187.2)	Labeled (related wording) related wording	serious n=201	not reported in cached trials
Chronic graft versus host disease	331	29.4 26.2–32.9ROR 29.5 · calibrated p 3e-4 ✓	26.7 EB05 24.4 · IC025 +4.5 3/3 methods agree vs other Kinase Inhibitors: PRR 84.3 (71.4–99.6)	Likely indication confounding term in indications; also in warnings	serious n=331	not reported in cached trials
Blast cell count increased	87	26.5 21.3–33.0ROR 26.5 · calibrated p 6e-4 ✓	24.3 EB05 20.3 · IC025 +4.1 3/3 methods agree vs other Kinase Inhibitors: only this drug	Lab value / disease marker	serious n=82 · ♀ 24% (drug 48%)	not reported in cached trials
Acute graft versus host disease in intestine	114	26.0 21.4–31.4ROR 26.0 · calibrated p 6e-4 ✓	23.8 EB05 20.4 · IC025 +4.1 3/3 methods agree vs other Kinase Inhibitors: PRR 688.4 (360.7–1,313.7)	Not in label — unassessed	serious n=114 · ♀ 22% (drug 48%) · 100% clinician	not reported in cached trials
Interleukin level increased	43	25.7 18.8–35.1ROR 25.7 · calibrated p 8e-4 ✓	23.5 EB05 18.2 · IC025 +3.7 3/3 methods agree vs other Kinase Inhibitors: only this drug	Lab value / disease marker	serious n=25 · ♀ 77% (drug 48%) · 100% clinician	not reported in cached trials
Essential thrombocythaemia	29	25.4 17.4–37.1ROR 25.4 · calibrated p 9e-4 ✓	23.1 EB05 16.8 · IC025 +3.5 3/3 methods agree vs other Kinase Inhibitors: only this drug	Likely indication confounding term in indications	serious n=28	not reported in cached trials
Haemoglobin abnormal	495	24.6 22.5–27.0ROR 24.8 · calibrated p 7e-4 ✓	22.8 EB05 21.1 · IC025 +4.3 3/3 methods agree vs other Kinase Inhibitors: PRR 101.7 (88.0–117.4)	Lab value / disease marker	serious n=200 · 83% consumer	not reported in cached trials
Early satiety	147	24.5 20.7–29.0ROR 24.6 · calibrated p 8e-4 ✓	22.6 EB05 19.7 · IC025 +4.1 3/3 methods agree vs other Kinase Inhibitors: PRR 1,479.4 (654.0–3,346.3)	Not in label — unassessed	serious n=72 · ♀ 28% (drug 48%)	not reported in cached trials

Trial evidence (ClinicalTrials.gov)

✓ Trial adverse-event data found on ClinicalTrials.gov

Largest completed trials with posted results that list Ruxolitinib as a study intervention. The right-hand column of the signal table shows whether each FAERS term was also recorded in these trials, with a real denominator (0 of 40 signal terms matched).

NCT03745638 — Topical Ruxolitinib Evaluation in Atopic Dermatitis Study 1 (TRuE AD1) - An Efficacy and Safety Study of Ruxol (N=631, PHASE3; 27 AE terms posted; arms: Vehicle Cream BID; Ruxolitinib 0.75% Cream BID; Ruxolitinib 1.5% Cream BID)
NCT03745651 — TRuE AD2 - An Efficacy and Safety Study of Ruxolitinib Cream in Adolescents and Adults With Atopic Dermatitis (N=618, PHASE3; 18 AE terms posted; arms: Vehicle Cream BID; Ruxolitinib 0.75% Cream BID; Ruxolitinib 1.5% Cream BID)

Caveats: trial populations, doses and follow-up differ from the reporting population; AE terms are sponsor-coded and matched here by wording; absence from a trial list means the term was not reported above the sponsor's frequency threshold, not that it cannot occur.

Most frequently reported reactions

By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.

Reaction	Reports	PRR 95% CI · ROR · χ²/p	EBGM EB05 · IC025	Label screen	Serious-only & strata	Trial cross-check
Off label use (used outside approved label)	14,560	5.0 4.9–5.1ROR 6.0 · calibrated p 0.148	4.9 EB05 4.9 · IC025 +2.3 3/3 methods agree vs other Kinase Inhibitors: PRR 45.0 (44.2–45.8)	Reporting / coding artifact	serious PRR 4.1 · 73% consumer	not reported in cached trials
Death	6,393	2.2 2.1–2.2ROR 2.3 · calibrated p 0.897	2.2 EB05 2.1 · IC025 +1.1 3/3 methods agree vs other Kinase Inhibitors: PRR 9.1 (8.9–9.3)	Outcome field, not a reaction	serious PRR 2.6	not reported in cached trials
Fatigue (tiredness)	6,114	2.3 2.3–2.4ROR 2.5 · calibrated p 0.834	2.3 EB05 2.3 · IC025 +1.2 3/3 methods agree vs other Kinase Inhibitors: PRR 10.2 (10.0–10.5)	Labeled adverse reaction exact term	serious PRR 2.1 · 75% consumer	not reported in cached trials
Anaemia (low red blood cells)	3,094	4.8 4.7–5.0ROR 5.0 · calibrated p 0.233	4.8 EB05 4.6 · IC025 +2.2 3/3 methods agree vs other Kinase Inhibitors: PRR 23.3 (22.4–24.2)	Labeled adverse reaction exact term	serious PRR 4.6	NCT03745638: 1/300 (0.3%) on Ruxolitinib (serious AE)
Haemoglobin decreased	2,961	8.7 8.4–9.0ROR 9.0 · calibrated p 0.045 ✓	8.5 EB05 8.2 · IC025 +3.0 3/3 methods agree vs other Kinase Inhibitors: PRR 34.6 (33.1–36.1)	Labeled (related wording) related wording	serious PRR 8.6	not reported in cached trials
Platelet count decreased	2,700	7.6 7.4–7.9ROR 7.9 · calibrated p 0.069	7.5 EB05 7.2 · IC025 +2.8 3/3 methods agree vs other Kinase Inhibitors: PRR 23.9 (22.9–25.0)	Labeled (related wording) related wording	serious PRR 7.8	not reported in cached trials
Diarrhoea (diarrhea)	2,683	1.2 1.2–1.3ROR 1.2 · calibrated p 0.466	1.2 EB05 1.2 · IC025 +0.2 vs other Kinase Inhibitors: PRR 5.3 (5.1–5.5)	Labeled adverse reaction exact term	serious PRR 1.3	not reported in cached trials
Product dose omission issue	2,653	2.8 2.7–2.9ROR 2.8 · calibrated p 0.685	2.7 EB05 2.7 · IC025 +1.4 3/3 methods agree vs other Kinase Inhibitors: PRR 33.7 (32.1–35.2)	Reporting / coding artifact	serious PRR 2.9 · 89% consumer	not reported in cached trials
Asthenia (weakness)	2,531	2.0 1.9–2.1ROR 2.0 · calibrated p 0.957	2.0 EB05 1.9 · IC025 +0.9 vs other Kinase Inhibitors: PRR 11.6 (11.1–12.1)	Not in label — unassessed	serious PRR 2.0 · 73% consumer	not reported in cached trials
Dizziness	2,494	1.5 1.4–1.5ROR 1.5 · calibrated p 0.638	1.5 EB05 1.4 · IC025 +0.5 vs other Kinase Inhibitors: PRR 20.6 (19.7–21.6)	Labeled adverse reaction exact term	serious PRR 1.4 · 73% consumer	NCT03745638: 1/300 (0.3%) on Ruxolitinib (serious AE)
Headache	2,425	1.1 1.1–1.2ROR 1.1 · calibrated p 0.403	1.1 EB05 1.1 · IC025 +0.1 vs other Kinase Inhibitors: PRR 16.2 (15.5–16.9)	Labeled adverse reaction exact term	serious PRR 1.1 · 71% consumer	NCT03745638: 16/300 (5.3%) on Ruxolitinib
Product availability issue	2,331	34.1 32.7–35.6ROR 35.2 · calibrated p 1e-4 ✓	30.6 EB05 29.6 · IC025 +4.9 3/3 methods agree vs other Kinase Inhibitors: PRR 1,058.3 (889.0–1,259.8)	Reporting / coding artifact	serious PRR 13.4 · ♀ 72% (drug 48%) · 86% consumer	not reported in cached trials
Drug ineffective (drug did not work)	2,172	0.5 0.5–0.5ROR 0.5 · calibrated p 0.039 ✓	0.5 EB05 0.5 · IC025 -1.1 PRR-only: not supported by EBGM or IC vs other Kinase Inhibitors: PRR 14.2 (13.6–14.9)	Reporting / coding artifact	serious PRR 1.1	not reported in cached trials
Pneumonia (lung infection)	2,170	2.0 1.9–2.1ROR 2.0 · calibrated p 0.951	2.0 EB05 1.9 · IC025 +0.9 vs other Kinase Inhibitors: PRR 14.2 (13.6–14.9)	Labeled (related wording) related wording	serious PRR 2.4	NCT03745638: 1/300 (0.3%) on Ruxolitinib (serious AE)
Nausea	2,155	0.8 0.8–0.8ROR 0.8 · calibrated p 0.182	0.8 EB05 0.8 · IC025 -0.4 PRR-only: not supported by EBGM or IC vs other Kinase Inhibitors: PRR 5.7 (5.4–5.9)	Labeled adverse reaction exact term	serious PRR 0.9	not reported in cached trials

Unlabeled candidate signals

These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.

Disease propensity — n=47, PRR 4,534.9
Aquagenic pruritus — n=48, PRR 463.1
Bronchiolitis obliterans syndrome — n=61, PRR 166.6
Chronic graft versus host disease in lung — n=56, PRR 146.0
Chronic graft versus host disease oral — n=42, PRR 62.3
Graft versus host disease in liver — n=109, PRR 53.1
Splenomegaly — n=1,764, PRR 52.2
Chronic graft versus host disease in intestine — n=25, PRR 45.5
Graft versus host disease in lung — n=63, PRR 44.9
Spleen disorder — n=194, PRR 37.8

Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.

Common questions

What are the most reported side effects of Ruxolitinib?

In FDA FAERS, the most frequently co-reported reaction terms for Ruxolitinib are fatigue, anaemia, haemoglobin decreased, platelet count decreased, diarrhoea, asthenia. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.

Does Ruxolitinib have an FDA boxed warning?

No. The FDA label retrieved for Ruxolitinib has no boxed warning; see the label's Warnings and Precautions for the recognised risks.

Do FAERS signals prove that Ruxolitinib causes these side effects?

No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.

Sources & methods

FDA label via openFDA (set ID f1c82580-87ae-11e0-bc84-0002a5d5c51b, effective 20260720; matched on openfda.generic_name.exact:"RUXOLITINIB")
Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA count= aggregation, field patient.drug.openfda.generic_name.exact, 1,205 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction
Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
Seriousness and sex counts from openFDA count=serious, patient.patientsex, seriousnessdeath
ClinicalTrials.gov API v2 (query RUXOLITINIB, results-bearing studies sorted by enrollment)

Page generated 2026-10-14. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.