Rheumatology
Rituximab
An anti-CD20 monoclonal antibody — A targeted "biologic" that depletes B-cells — used in some cancers and autoimmune diseases.
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
Quick answer
What is Rituximab?
Rituximab is a targeted antibody treatment that removes a type of immune cell (B-cells). It is used in certain blood cancers (such as some lymphomas and leukaemias) and in several antibody-driven autoimmune diseases.
- How it works: It binds a marker (CD20) on the surface of B-cells and flags them for destruction, depleting them from the blood.
- In practice: In practice rituximab is given by infusion to deplete the B-cells that drive certain lymphomas and leukaemias and several antibody-mediated autoimmune diseases (such as some rheumatoid arthritis, vasculitis and others).
What it is
Rituximab is a targeted antibody treatment that removes a type of immune cell (B-cells). It is used in certain blood cancers (such as some lymphomas and leukaemias) and in several antibody-driven autoimmune diseases. It is given by infusion under specialist care.
How it works
It binds a marker (CD20) on the surface of B-cells and flags them for destruction, depleting them from the blood. Removing these cells reduces the abnormal antibodies and inflammation that drive the disease — but also blunts part of the body's defence against infection.
In practice
In practice rituximab is given by infusion to deplete the B-cells that drive certain lymphomas and leukaemias and several antibody-mediated autoimmune diseases (such as some rheumatoid arthritis, vasculitis and others). Two safety themes dominate. First, infusion reactions: these are commonest with the first infusion, so premedication is given and the infusion is run carefully with monitoring. Second, infection: by removing B-cells it weakens part of the immune defence, so patients are screened for hepatitis B (which it can reactivate, sometimes severely) and other infections before treatment, kept up to date with appropriate vaccinations beforehand, and told to report signs of infection; live vaccines are avoided. Effects on the immune system and on antibody levels can persist for many months after the last dose, so vigilance continues well beyond treatment. It is always specialist-initiated and supervised.
Examples
Practical use
How to take it & use it well
- Rituximab is given as a slow drip (infusion) into a vein by trained staff in a clinic or hospital, not taken at home.
- You will usually be given premedication beforehand to lower the chance of an infusion reaction, especially with the first dose.
- Tell the staff straight away during the infusion if you feel unwell, flushed, itchy, breathless or shivery, as the rate can be adjusted or paused.
- Before starting, you will be screened for infections including hepatitis B, because the treatment can reactivate it; report any signs of infection during treatment.
- Its effects last many months after each course, so keep follow-up appointments and tell any clinician you have had it, even long afterwards.
Common uses
- Some B-cell lymphomas and leukaemias
- Rheumatoid arthritis and ANCA-associated vasculitis (and other autoimmune diseases)
- Other antibody-mediated conditions (specialist)
Monitoring
- Hepatitis B and infection screening before treatment; vaccination review
- During-infusion monitoring for reactions; signs of infection throughout
- Antibody (immunoglobulin) levels and blood counts over time
Weighing it up
Advantages & disadvantages
Advantages
- It targets and depletes B-cells, treating certain lymphomas and leukaemias as well as autoimmune conditions like rheumatoid arthritis and vasculitis.
- A course can control disease for many months, reducing how often treatment is needed.
- It offers an option when other treatments have not worked well enough.
- It is given under close supervision, so reactions can be managed quickly.
Disadvantages
- Infusion reactions can occur, particularly with the first dose, and require monitoring and premedication.
- It increases infection risk and can reactivate hidden infections such as hepatitis B.
- Its long-lasting effect on the immune system means vaccine planning and infection vigilance are needed for months.
- It must be given in a clinical setting, which takes time and planning.
Key safety principles
What to watch for
- Infusion reactions — commonest with the first infusion; premedication and careful monitoring are used.
- Infection risk — screen for hepatitis B (reactivation risk) and other infections before treatment; avoid live vaccines; update vaccines beforehand.
- Immune effects (low antibodies, infection risk) can persist for many months after the last dose.
Key interactions
What to avoid or check alongside
- Live vaccines should be avoided around and after treatment, because the weakened immune system makes them unsafe and less effective.
- Combining it with other immune-suppressing medicines further raises infection risk.
- Hepatitis B can reactivate, so screening and sometimes antiviral cover are arranged before treatment.
- Tell your clinician about all medicines and any recent or planned vaccinations so timing can be managed safely.
Patient & carer advice
- Report any reaction during or after the infusion, and any signs of infection promptly
- Avoid live vaccines and tell vaccinators you have had this
- Carry a biologics/treatment alert card; effects on your immune system last months
Use with
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Answers
Rituximab: frequently asked questions
Why am I given medicines before the rituximab infusion?
Premedication helps reduce the risk and severity of infusion reactions, which are most likely with the first dose. Staff also slow or pause the infusion if you react.
Why do I need a hepatitis B test before starting?
Rituximab can reactivate a past or hidden hepatitis B infection, which can be serious. Screening lets your team protect you, sometimes with antiviral medicine, before treatment.
Can I have vaccinations while on rituximab?
Live vaccines should be avoided, and other vaccines may work less well because the treatment lowers your immune response. Discuss any planned vaccines with your clinician first.
How long does rituximab stay working?
Its effect on your immune system lasts many months after a course. Because of this, you should mention having had it to any healthcare professional for some time afterwards.
What should I do if I think I have an infection during treatment?
Contact your clinical team promptly, as rituximab raises your infection risk. Early treatment of infections is important while your immune system is suppressed.
Authoritative sources
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