Rituximab-Arrx: uses, dosing, side effects & brands
Rituximab-Arrx is a medicine sold in the U.S. under one brand, for rheumatoid arthritis, lymphoid leukemia and granulomatosis with polyangiitis. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Treats
- Rheumatoid Arthritis, Lymphoid Leukemia and Granulomatosis with Polyangiitis
- Available as
- Injectable
- Sold as
- Riabni
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
- Boxed warning
- Boxed warning
How rituximab-arrx is dosed
From the FDA label for Riabni (application BLA761140). Other rituximab-arrx products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Administer only as an intravenous infusion ( 2.1 ). Do not administer as an intravenous push or bolus ( 2.1 ). RIABNI should only be administered by a healthcare professional with appropriate medical support to manage severe infusion-related reactions that can be fatal if they occur ( 2.1 ). The dose for adult B-cell NHL is 375 mg/m 2 ( 2.2 ). The dose for CLL is 375 mg/m 2 in the first cycle and 500 mg/m 2 in cycles 2–6, in combination with FC, administered every 28 days ( 2.3 ). The dose as a component of Zevalin ® (ibritumomab tiuxetan) Therapeutic Regimen is 250 mg/m 2 ( 2.4 ). The dose for RA in combination with methotrexate is two-1,000 mg intravenous infusions separated by 2 weeks (one course) every 24 weeks or based on clinical evaluation, but not sooner than every 16 weeks. Methylprednisolone 100 mg intravenous or equivalent glucocorticoid is recommended 30 minutes prior to each infusion ( 2.5 ). The induction dose for adult patients with active GPA and MPA in combination with glucocorticoids is 375 mg/m 2 once weekly for 4 weeks. The follow up dose for adult patients with GPA and MPA who have achieved disease control with induction treatment, in combination with glucocorticoids is two 500 mg intravenous infusions separated by two weeks, followed by a 500 mg intravenous infusion every 6 months thereafter based on clinical evaluation ( 2.6 ). The dose for PV is…
Rituximab-Arrx side effects
The following clinically significant adverse reactions are discussed in greater detail in other sections of the labeling: Infusion-related reactions [see Warnings and Precautions (5.1) ] Severe mucocutaneous reactions [see Warnings and Precautions (5.2) ] Hepatitis B reactivation with fulminant hepatitis [see Warnings and Precautions (5.3) ] Progressive multifocal leukoencephalopathy [see Warnings and Precautions (5.4) ] Tumor lysis syndrome [see Warnings and Precautions (5.5) ] Infections [see Warnings and Precautions (5.6) ] Cardiovascular adverse reactions [see Warnings and Precautions (5.7) ] Renal toxicity [see Warnings and Precautions (5.8) ] Bowel obstruction and perforation [see Warnings and Precautions (5.9) ] Most common adverse reactions in clinical trials were: NHL (greater than or equal to 25%): infusion-related reactions, fever, lymphopenia, chills, infection, and asthenia ( 6.1 ). CLL (greater than or equal to 25%): infusion-related reactions and neutropenia ( 6.1 ). RA (greater than or equal to 10%): upper respiratory tract infection, nasopharyngitis, urinary tract infection, and bronchitis (other important adverse reactions include infusion-related reactions, serious infections, and cardiovascular events) ( 6.1 ). GPA and MPA (greater than or equal to 15%): infections, nausea, diarrhea, headache, muscle spasms, anemia, peripheral edema, infusion-related…
Who shouldn’t take rituximab-arrx
None. None ( 4 )
Rituximab-Arrx drug interactions
Formal drug interaction studies have not been performed with rituximab products. In patients with CLL, rituximab did not alter systemic exposure to fludarabine or cyclophosphamide. In clinical trials of patients with RA, concomitant administration of methotrexate or cyclophosphamide did not alter the pharmacokinetics of rituximab. Renal toxicity when used in combination with cisplatin ( 5.8 ).
Every rituximab-arrx product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Riabni.
What people report to the FDA about rituximab-arrx
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 4 reports naming rituximab-arrx, and the FDA flagged 100% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- blood immunoglobulin m decreased1 reports
- chest discomfort1 reports
- colitis1 reports
- infusion related reaction1 reports
- lower respiratory tract infection1 reports
- neutropenia1 reports
- sepsis1 reports
- skin infection1 reports
Read these as a signal, not a rate. A report does not mean rituximab-arrx caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 26, 2026.
Related calculators
Frequently asked questions
What is rituximab-arrx?
Riabni (Rituximab-Arrx) is a medication used to treat Rheumatoid Arthritis, Lymphoid Leukemia, Granulomatosis with Polyangiitis, B-Cell Lymphoma.
Can you take rituximab-arrx with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run rituximab-arrx against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does rituximab-arrx come in?
Across the brands we track, rituximab-arrx is currently marketed as injectable, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic rituximab-arrx?
We do not currently list a generic-labelled rituximab-arrx product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Rituximab-Arrx: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/rituximab-arrx
- MLA
- “Rituximab-Arrx: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/rituximab-arrx.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for rituximab-arrx on DailyMed (NIH) ↗ — including its boxed warning in full.