Drug · FAERS side-effect profile with label screen
Rituximab side effects: what 210,132 FDA adverse event reports show
Drug class
CD20-directed Cytolytic Antibody
FDA label (Established Pharmacologic Class) · compare the class
Brand names
Rituxan
openFDA label
Who reports
210,132 reports · 89% serious · 37,069 with death outcome · 59% female
openFDA FAERS counts, all years, deduplication not applied
Used for
RITUXAN is a CD20-directed cytolytic antibody indicated for the treatment of: Adult patients with Non-Hodgkin's Lymphoma (NHL) ( 1.1 ). Relapsed or refractory, low grade or follicular, CD20-positive B-cell NHL as a single agent. Previously untreated fo.
FDA label, Indications and Usage
What it is
Rituximab is a genetically engineered chimeric murine/human monoclonal IgG 1 kappa antibody directed against the CD20 antigen. Rituximab has an approximate molecular weight of 145 kD. Rituxima.
FDA label, Description section
Boxed warning
FATAL INFUSION-RELATED REACTIONS, SEVERE MUCOCUTANEOUS REACTIONS, HEPATITIS B VIRUS REACTIVATION and PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY WARNING: FATAL INFUSION-RELATED REACTIONS, SEVERE MUCOCUTANEOUS REACTIONS, HEPATITIS B VIRUS REACTIVATION and PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY See full prescribing information for complete boxed warning.
FDA 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 — boxed warning 1Labeled adverse reaction 1Labeled (related wording) 6Likely indication confounding 7Lab value / disease marker 10Not in label — unassessed 15
What the badges mean
- Labeled — boxed warning The term (or its clinical synonym) appears in the FDA boxed warning: causality is regulator-recognised and considered serious.
- 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.
- 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). 1,252 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
Show:
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Anti-cyclic citrullinated peptide antibody positive | 5,755 | 445.1 418.9–473.1ROR 457.7 · calibrated p 1e-13 ✓ | 80.8 EB05 79.0 · IC025 +6.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious PRR 52.1 · ♀ 99% (drug 59%) · 92% clinician | not reported in cached trials |
| Pemphigus | 9,375 | 315.6 302.8–329.0ROR 330.3 · calibrated p 4e-12 ✓ | 75.2 EB05 73.9 · IC025 +6.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 938.7 (795.7–1,107.3) | Likely indication confounding term in indications; also in warnings | serious PRR 48.5 · ♀ 98% (drug 59%) | not reported in cached trials |
| Red blood cell sedimentation rate | 211 | 306.9 233.2–404.0ROR 307.2 · calibrated p 2e-11 ✓ | 74.2 EB05 66.2 · IC025 +5.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=211 · ♀ 100% (drug 59%) · 90% clinician | not reported in cached trials |
| Swollen joint count increased | 2,326 | 301.1 277.3–326.8ROR 304.4 · calibrated p 9e-12 ✓ | 74.3 EB05 71.8 · IC025 +6.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=2,324 · ♀ 100% (drug 59%) · 96% clinician | not reported in cached trials |
| Rheumatic fever | 3,199 | 280.1 261.7–299.9ROR 284.4 · calibrated p 2e-11 ✓ | 73.0 EB05 70.9 · IC025 +6.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled (related wording) related wording | serious n=3,198 · ♀ 100% (drug 59%) · 94% clinician | not reported in cached trials |
| Vaccine interaction | 227 | 280.0 216.8–361.7ROR 280.3 · calibrated p 4e-11 ✓ | 72.6 EB05 65.0 · IC025 +5.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | 100% clinician | not reported in cached trials |
| Rheumatoid factor positive | 4,177 | 268.2 252.9–284.4ROR 273.6 · calibrated p 2e-11 ✓ | 72.2 EB05 70.4 · IC025 +6.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=4,175 · ♀ 98% (drug 59%) · 93% clinician | not reported in cached trials |
| Swollen joint count | 176 | 256.0 193.2–339.2ROR 256.2 · calibrated p 9e-11 ✓ | 70.8 EB05 62.4 · IC025 +5.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=175 · ♀ 100% (drug 59%) · 100% clinician | not reported in cached trials |
| C-reactive protein | 640 | 243.7 210.8–281.6ROR 244.4 · calibrated p 8e-11 ✓ | 70.2 EB05 65.7 · IC025 +5.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=640 · ♀ 100% (drug 59%) · 96% clinician | NCT01071798: 1/1,653 (0.1%) on Rituximab (serious AE) |
| Lupus vulgaris | 827 | 231.6 204.4–262.5ROR 232.5 · calibrated p 1e-10 ✓ | 69.2 EB05 65.3 · IC025 +5.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled (related wording) related wording | serious n=827 · ♀ 100% (drug 59%) · 96% clinician | not reported in cached trials |
| Duodenal ulcer perforation | 4,935 | 208.1 198.1–218.6ROR 213.1 · calibrated p 2e-10 ✓ | 67.0 EB05 65.5 · IC025 +6.0 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled — boxed warning synonym match | serious PRR 43.1 · ♀ 100% (drug 59%) · 94% clinician | not reported in cached trials |
| Deep vein thrombosis postoperative | 1,318 | 207.9 188.9–228.7ROR 209.2 · calibrated p 3e-10 ✓ | 67.0 EB05 64.0 · IC025 +5.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=1,318 · ♀ 100% (drug 59%) · 93% clinician | not reported in cached trials |
| Diffuse large b-cell lymphoma recurrent | 1,437 | 205.1 187.2–224.6ROR 206.5 · calibrated p 3e-10 ✓ | 66.7 EB05 63.8 · IC025 +5.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled (related wording) related wording | serious n=1,428 | not reported in cached trials |
| Facet joint syndrome | 2,003 | 176.0 163.6–189.4ROR 177.7 · calibrated p 1e-9 ✓ | 63.3 EB05 61.0 · IC025 +5.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=2,002 · ♀ 100% (drug 59%) · 95% clinician | not reported in cached trials |
| Chronic lymphocytic leukaemia recurrent | 429 | 164.0 140.4–191.4ROR 164.3 · calibrated p 3e-9 ✓ | 61.6 EB05 56.9 · IC025 +5.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Likely indication confounding shares a disease stem with the indications wording | serious n=423 · ♀ 32% (drug 59%) | not reported in cached trials |
| Anti-cyclic citrullinated peptide antibody | 410 | 160.5 137.1–187.8ROR 160.8 · calibrated p 3e-9 ✓ | 61.1 EB05 56.3 · IC025 +5.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=410 · ♀ 100% (drug 59%) · 95% clinician | not reported in cached trials |
| Mantle cell lymphoma recurrent | 263 | 160.2 131.6–195.0ROR 160.4 · calibrated p 4e-9 ✓ | 61.0 EB05 55.0 · IC025 +5.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Likely indication confounding shares a disease stem with the indications wording | serious n=263 · ♀ 39% (drug 59%) | not reported in cached trials |
| Granuloma skin | 507 | 158.9 138.0–183.0ROR 159.3 · calibrated p 3e-9 ✓ | 60.9 EB05 56.6 · IC025 +5.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled (related wording) related wording | serious n=507 · ♀ 92% (drug 59%) | not reported in cached trials |
| B-cell lymphoma recurrent | 325 | 150.8 126.8–179.4ROR 151.1 · calibrated p 5e-9 ✓ | 59.6 EB05 54.4 · IC025 +5.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Likely indication confounding shares a disease stem with the indications wording | serious n=320 · ♀ 34% (drug 59%) | not reported in cached trials |
| Grip strength | 139 | 150.5 115.5–196.2ROR 150.6 · calibrated p 8e-9 ✓ | 59.3 EB05 51.5 · IC025 +5.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=139 · ♀ 100% (drug 59%) · 100% clinician | not reported in cached trials |
| Blood pressure diastolic abnormal | 1,522 | 146.1 135.0–158.2ROR 147.2 · calibrated p 6e-9 ✓ | 59.0 EB05 56.6 · IC025 +5.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=1,427 · 90% clinician | not reported in cached trials |
| Lymphoma transformation | 212 | 143.5 116.1–177.3ROR 143.6 · calibrated p 9e-9 ✓ | 58.3 EB05 52.0 · IC025 +5.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Likely indication confounding shares a disease stem with the indications wording | serious n=210 · ♀ 0% (drug 59%) | not reported in cached trials |
| Hand deformity | 7,685 | 143.3 138.4–148.3ROR 148.7 · calibrated p 5e-9 ✓ | 58.6 EB05 57.5 · IC025 +5.8 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 728.4 (620.0–855.7) | Not in label — unassessed | serious PRR 41.0 · ♀ 98% (drug 59%) · 91% clinician | not reported in cached trials |
| Blood pressure systolic abnormal | 1,413 | 131.8 121.7–142.7ROR 132.7 · calibrated p 1e-8 ✓ | 56.6 EB05 54.1 · IC025 +5.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=1,328 · 90% clinician | not reported in cached trials |
| Humoral immune defect | 207 | 126.1 102.6–155.0ROR 126.2 · calibrated p 3e-8 ✓ | 55.3 EB05 49.2 · IC025 +5.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=187 · 100% clinician | not reported in cached trials |
| X-ray abnormal | 966 | 118.3 107.7–129.9ROR 118.8 · calibrated p 3e-8 ✓ | 53.9 EB05 51.1 · IC025 +5.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=966 · ♀ 95% (drug 59%) · 93% clinician | not reported in cached trials |
| Adjustment disorder with depressed mood | 1,074 | 114.3 104.6–124.8ROR 114.9 · calibrated p 4e-8 ✓ | 53.1 EB05 50.5 · IC025 +5.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=1,074 · ♀ 100% (drug 59%) · 95% clinician | not reported in cached trials |
| Helicobacter infection | 5,074 | 99.1 95.4–103.1ROR 101.6 · calibrated p 1e-7 ✓ | 49.6 EB05 48.5 · IC025 +5.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 398.6 (343.8–462.0) | Not in label — unassessed | serious PRR 33.8 · ♀ 100% (drug 59%) · 93% clinician | not reported in cached trials |
| Dislocation of vertebra | 1,091 | 96.2 88.5–104.6ROR 96.7 · calibrated p 2e-7 ✓ | 48.9 EB05 46.5 · IC025 +5.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=1,091 · ♀ 95% (drug 59%) · 95% clinician | not reported in cached trials |
| Synovitis | 8,767 | 94.5 91.8–97.3ROR 98.5 · calibrated p 1e-7 ✓ | 48.5 EB05 47.6 · IC025 +5.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 769.4 (659.0–898.3) | Not in label — unassessed | serious PRR 32.6 · ♀ 93% (drug 59%) | NCT01071798: 1/820 (0.1%) on Rituximab (serious AE) |
| Diffuse large b-cell lymphoma refractory | 450 | 93.7 82.3–106.7ROR 93.9 · calibrated p 2e-7 ✓ | 48.2 EB05 44.6 · IC025 +5.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Likely indication confounding term in indications; also in warnings | serious n=449 · 90% clinician | not reported in cached trials |
| C-reactive protein abnormal | 3,054 | 91.0 86.7–95.6ROR 92.4 · calibrated p 2e-7 ✓ | 47.5 EB05 46.1 · IC025 +5.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Lab value / disease marker | serious n=3,050 · ♀ 92% (drug 59%) | NCT01071798: 1/1,653 (0.1%) on Rituximab (serious AE) |
| Subcutaneous drug absorption impaired | 257 | 89.1 75.3–105.6ROR 89.2 · calibrated p 3e-7 ✓ | 46.9 EB05 42.3 · IC025 +5.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=256 · ♀ 100% (drug 59%) · 100% clinician | not reported in cached trials |
| Hypocholesterolaemia | 141 | 84.3 67.3–105.6ROR 84.4 · calibrated p 5e-7 ✓ | 45.4 EB05 39.5 · IC025 +5.0 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=141 · ♀ 100% (drug 59%) · 100% clinician | not reported in cached trials |
| Muscle injury | 3,701 | 82.0 78.5–85.6ROR 83.4 · calibrated p 4e-7 ✓ | 45.0 EB05 43.8 · IC025 +5.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious PRR 31.4 · ♀ 100% (drug 59%) · 94% clinician | not reported in cached trials |
| Follicular lymphoma | 383 | 81.3 71.0–93.1ROR 81.5 · calibrated p 6e-7 ✓ | 44.7 EB05 41.1 · IC025 +5.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled adverse reaction exact term | serious n=373 | not reported in cached trials |
| Retinitis | 721 | 75.8 68.8–83.5ROR 76.1 · calibrated p 9e-7 ✓ | 43.0 EB05 40.5 · IC025 +5.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Not in label — unassessed | serious n=721 · ♀ 100% (drug 59%) · 95% clinician | not reported in cached trials |
| Sleep disorder due to general medical condition, insomnia type | 2,715 | 72.7 69.2–76.4ROR 73.6 · calibrated p 1e-6 ✓ | 42.1 EB05 40.7 · IC025 +5.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled (related wording) related wording | serious n=2,713 · ♀ 98% (drug 59%) · 95% clinician | not reported in cached trials |
| Folliculitis | 4,291 | 70.8 68.1–73.7ROR 72.3 · calibrated p 1e-6 ✓ | 41.4 EB05 40.4 · IC025 +5.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 476.6 (400.0–568.0) | Likely indication confounding shares a disease stem with the indications wording | serious PRR 31.3 · ♀ 100% (drug 59%) · 94% clinician | not reported in cached trials |
| Peripheral venous disease | 1,611 | 67.4 63.2–71.8ROR 67.9 · calibrated p 2e-6 ✓ | 40.2 EB05 38.6 · IC025 +5.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: only this drug | Labeled (related wording) related wording | serious n=1,610 · ♀ 100% (drug 59%) · 95% clinician | not reported in cached trials |
Clinical concept groups
MedDRA splits one clinical problem across several terms (e.g. "neutropenia", "neutrophil count decreased", "agranulocytosis"), which dilutes term-level signals. These rows count reports with any term in a concept group (an exact union, not a sum), compared with all other drugs. Groups are hand-built and listed in the methods.
| Concept | Reports | PRR 95% CI | Reading |
|---|---|---|---|
| Neutropenia / agranulocytosis | 17,178 | 7.47.3–7.5 | signal |
| Interstitial lung disease | 6,312 | 7.06.8–7.1 | signal |
| Opportunistic infection | 8,168 | 6.36.2–6.4 | signal |
| Liver injury | 15,557 | 5.45.3–5.5 | signal |
| Thrombocytopenia | 9,232 | 4.34.2–4.4 | signal |
| Serious infection | 30,857 | 4.14.1–4.2 | signal |
| Anaemia | 7,846 | 2.72.6–2.7 | signal |
| Anaphylaxis / angioedema | 2,486 | 2.01.9–2.1 | raised |
| Venous thromboembolism | 4,059 | 1.91.8–1.9 | raised |
| Hyperglycaemia / diabetes | 6,372 | 1.91.8–1.9 | raised |
| Kidney injury | 7,748 | 1.71.7–1.7 | raised |
| Arrhythmia / qt | 3,269 | 1.71.6–1.8 | raised |
| Malignancy | 4,984 | 1.31.3–1.4 | raised |
| Tendon disorder | 503 | 1.31.2–1.4 | raised |
| Heart failure | 2,340 | 1.31.3–1.4 | raised |
| Pancreatitis | 989 | 1.21.2–1.3 | raised |
Trial evidence (ClinicalTrials.gov)
✓ Trial adverse-event data found on ClinicalTrials.gov
Largest completed trials with posted results that list Rituximab 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 (3 of 40 signal terms matched).
- NCT01071798 — An Observational Study on the Safety and Effectiveness of Rituximab in Patients With Severe Active Rheumatoid (N=1653, phase n/a; 223 AE terms posted; arms: Cycle 1; Cycle 2; Total)
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) | 40,662 | 4.9 4.8–4.9ROR 5.8 · calibrated p 0.165 | 4.7 EB05 4.6 · IC025 +2.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 79.9 (78.2–81.6) | Reporting / coding artifact | age-adj. PRR 4.5 · serious PRR 4.6 | not reported in cached trials |
| Drug ineffective (drug did not work) | 34,032 | 2.6 2.6–2.6ROR 2.9 · calibrated p 0.648 | 2.6 EB05 2.6 · IC025 +1.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 131.7 (127.6–135.9) | Reporting / coding artifact | age-adj. PRR 3.2 · serious PRR 4.5 | NCT01071798: 1/1,653 (0.1%) on Rituximab (serious AE) |
| Rheumatoid arthritis | 20,084 | 21.4 21.1–21.7ROR 23.5 · calibrated p 9e-4 ✓ | 17.7 EB05 17.5 · IC025 +4.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 603.7 (551.6–660.7) | Likely indication confounding term in indications; also in warnings | age-adj. PRR 19.1 · serious PRR 13.8 · ♀ 93% (drug 59%) | NCT01071798: 7/1,653 (0.4%) on Rituximab (serious AE) |
| Pain | 17,703 | 2.9 2.9–3.0ROR 3.1 · calibrated p 0.593 | 2.9 EB05 2.8 · IC025 +1.5 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 39.3 (38.3–40.3) | Labeled — boxed warning exact term | age-adj. PRR 2.9 · serious PRR 2.8 · ♀ 90% (drug 59%) | NCT01071798: 1/1,653 (0.1%) on Rituximab (serious AE) |
| Fatigue (tiredness) | 17,224 | 2.2 2.2–2.3ROR 2.4 · calibrated p 0.879 | 2.2 EB05 2.2 · IC025 +1.1 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 20.2 (19.8–20.5) | Labeled adverse reaction exact term | age-adj. PRR 2.0 · serious PRR 2.6 · ♀ 87% (drug 59%) | not reported in cached trials |
| Rash | 13,454 | 3.2 3.1–3.2ROR 3.3 · calibrated p 0.533 | 3.1 EB05 3.1 · IC025 +1.6 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 93.9 (89.7–98.2) | Labeled adverse reaction exact term | age-adj. PRR 2.9 · serious PRR 4.2 · ♀ 89% (drug 59%) | NCT01071798: 2/1,653 (0.1%) on Rituximab (serious AE) |
| Arthralgia (joint pain) | 13,299 | 3.3 3.2–3.3ROR 3.4 · calibrated p 0.502 | 3.2 EB05 3.2 · IC025 +1.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 76.4 (73.3–79.6) | Labeled adverse reaction exact term | age-adj. PRR 3.1 · serious PRR 3.7 · ♀ 88% (drug 59%) | NCT01071798: 2/820 (0.2%) on Rituximab (serious AE) |
| Pneumonia (lung infection) | 12,911 | 4.1 4.0–4.2ROR 4.3 · calibrated p 0.324 | 4.0 EB05 3.9 · IC025 +2.0 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 52.8 (51.0–54.7) | Labeled — boxed warning synonym match | age-adj. PRR 3.7 · serious PRR 2.7 | NCT01071798: 11/1,653 (0.7%) on Rituximab (serious AE) |
| Infusion related reaction (reaction during infusion) | 12,680 | 23.5 23.1–24.0ROR 25.0 · calibrated p 7e-4 ✓ | 19.2 EB05 18.9 · IC025 +4.2 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 43.6 (42.2–45.1) | Labeled — boxed warning synonym match | age-adj. PRR 21.1 · serious PRR 14.7 · ♀ 87% (drug 59%) | NCT01071798: 1/1,653 (0.1%) on Rituximab (serious AE) |
| Drug intolerance | 12,498 | 14.8 14.5–15.0ROR 15.6 · calibrated p 0.006 ✓ | 13.0 EB05 12.8 · IC025 +3.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 413.2 (375.7–454.5) | Reporting / coding artifact | age-adj. PRR 17.1 · serious PRR 13.4 · ♀ 90% (drug 59%) | not reported in cached trials |
| Joint swelling | 11,848 | 10.8 10.6–11.0ROR 11.4 · calibrated p 0.020 ✓ | 9.8 EB05 9.7 · IC025 +3.3 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 330.3 (302.6–360.6) | Not in label — unassessed | age-adj. PRR 9.9 · serious PRR 10.8 · ♀ 92% (drug 59%) | not reported in cached trials |
| Pyrexia (fever) | 11,717 | 3.5 3.4–3.5ROR 3.6 · calibrated p 0.459 | 3.4 EB05 3.3 · IC025 +1.7 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 29.8 (28.9–30.6) | Labeled adverse reaction exact term | age-adj. PRR 3.1 · serious PRR 2.6 | NCT01071798: 2/1,653 (0.1%) on Rituximab (serious AE) |
| Nausea | 11,640 | 1.5 1.5–1.5ROR 1.5 · calibrated p 0.646 | 1.5 EB05 1.4 · IC025 +0.5 vs other CD20-directed Cytolytic Antibodys: PRR 46.1 (44.5–47.7) | Labeled adverse reaction exact term | age-adj. PRR 1.4 · serious PRR 1.7 · ♀ 82% (drug 59%) | NCT01071798: 2/1,653 (0.1%) on Rituximab (serious AE) |
| Infection | 11,043 | 8.2 8.0–8.4ROR 8.6 · calibrated p 0.053 | 7.6 EB05 7.5 · IC025 +2.9 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 75.6 (72.3–79.1) | Labeled — boxed warning exact term | age-adj. PRR 6.6 · serious PRR 6.0 · ♀ 81% (drug 59%) | NCT01071798: 1/1,653 (0.1%) on Rituximab (serious AE) |
| Alopecia (hair loss) | 10,833 | 5.8 5.7–5.9ROR 6.0 · calibrated p 0.149 | 5.5 EB05 5.4 · IC025 +2.4 3/3 methods agree vs other CD20-directed Cytolytic Antibodys: PRR 91.1 (86.7–95.8) | Labeled adverse reaction exact term | age-adj. PRR 4.7 · serious PRR 7.4 · ♀ 98% (drug 59%) | NCT01071798: 1/820 (0.1%) on Rituximab (serious AE) |
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.
- Vaccine interaction — n=227, PRR 280.0
- Swollen joint count — n=176, PRR 256.0
- Deep vein thrombosis postoperative — n=1,318, PRR 207.9
- Facet joint syndrome — n=2,003, PRR 176.0
- Grip strength — n=139, PRR 150.5
- Hand deformity — n=7,685, PRR 143.3
- Humoral immune defect — n=207, PRR 126.1
- Adjustment disorder with depressed mood — n=1,074, PRR 114.3
- Helicobacter infection — n=5,074, PRR 99.1
- Dislocation of vertebra — n=1,091, PRR 96.2
✓ A hand-written Bradford Hill causality assessment exists for this drug: Rituximab ↔ Serious infection.
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 Rituximab?
In FDA FAERS, the most frequently co-reported reaction terms for Rituximab are rheumatoid arthritis, pain, fatigue, rash, arthralgia, pneumonia. 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 Rituximab have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: FATAL INFUSION-RELATED REACTIONS, SEVERE MUCOCUTANEOUS REACTIONS, HEPATITIS B VIRUS REACTIVATION and PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY WARNING: FATAL INFUSION-RELATED REACTIONS, SEVERE MUCOCUTANEOUS REACTIONS, HEPATITIS B VIRUS REACTIVATION and PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY See full prescribing information for complete boxed warning.
Do FAERS signals prove that Rituximab 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 b172773b-3905-4a1c-ad95-bab4b6126563, effective 20250106; matched on
openfda.generic_name.exact:"RITUXIMAB" AND openfda.product_type:"HUMAN PRESCRIPTION DRUG") - 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, fieldpatient.drug.openfda.generic_name.exact, 1,292 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
RITUXIMAB, 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.