Rituximab (Rituxan & MabThera)

Rituximab is a drug used to treat rheumatoid arthritis that has not improved with other types of medications, as well as certain forms of vasculitis. It works by turning off a part of the immune system that is not working properly in autoimmune diseases. Rituximab is used in combination other DMARD (disease modifying anti-rheumatic drugs) or can be used in treatment on its own. Rituximab has been used to treat rheumatoid arthritis and also is used to treat certain types of vasculitis (an condition affecting blood vessels), such as granulomatosis with polyangiitis or microscopic polyangiitis.

Occasionally rituximab is used to treat other immune problems, including systemic lupus erythematosus, and inflammatory myositis and blood conditions such as chronic lymphocytic leukemia, non-Hodgkin’s lymphoma, and idiopathic thrombocytopenia (ITP).

How to Take It

Rituximab is a liquid given through a vein (IV). The treatment usually takes two to four hours, although occasionally it can take longer. A course of rituximab for rheumatoid arthritis usually consists of two 1000 mg doses given 15 days apart. To treat vasculitis, a smaller dose is given once a week for four weeks in a row.

Side Effects

Mild side effects during or up to 24 hours after receiving rituximab may occur. These usually occur with the first infusion, and can include mild throat tightening, flu-like symptoms, rash, itchiness, dizziness, back pain, nausea, upset stomach, sweating, nervousness, muscle stiffness, and numbness. These symptoms can be reduced by receiving a steroid injection before the infusion, along with acetaminophen and diphenhydramine. The treatment is sometimes stopped for a short while and then restarted at a slower rate if the symptoms get better. Rarely, patients will have more serious symptoms, such as wheezing, mouth or throat swelling, trouble breathing, or chest pain. Patients who experience these symptoms should tell their rheumatology providers immediately; In the months after the treatment, some people may notice more frequent infections, such as colds or sinus congestion. There are a few rare but serious side effects from rituximab. Patients who experience vision changes, loss of balance, difficulty walking, confusion, skin reactions, or mouth sores should contact their rheumatology team immediately.

Tell Your Rheumatology Provider

Tell your rheumatology provider if you have lung or heart problems or have ever had any major infections (especially hepatitis). Patients who may become pregnant should consider using birth control during therapy and 12 months following the end of the treatment. Based on limited data, rituximab can be used before pregnancy if no other medications can be used but should be discontinued once pregnancy is confirmed. Rituximab is present in breast milk, and in general breast feeding is not recommended during treatment and for 6 months after the last treatment. However, limited data does report that rituximab is unlikely absorbed by the baby’s stomach and intestines. Vaccines are not as effective for several months after receiving rituximab, so you should receive necessary ones before starting treatment or between courses.

Updated February 2024 by Mohammad Ursani, MD, and reviewed by the American College of Rheumatology Communications and Marketing Committee.

This information is provided for general education only. Individuals should consult a qualified health care provider for professional medical advice, diagnosis, and treatment of a medical or health condition.