What is the most important information I should know about rituximab?

You should not receive this medication if you have ever had a severe allergic reaction to rituximab, or if you are allergic to mouse protein.

Some people receiving a rituximab injection have had a reaction to the infusion (when the medicine is injected into the vein). Tell your caregiver right away if you feel dizzy, weak, nauseated, light-headed, itchy, or if you have a fever, chills, muscle pain, sneezing, sore throat, trouble breathing, or pain in your chest or shoulders. Infusion reactions often occur within the first 24 hours after the start of your rituximab infusion.

To be sure this medication is not causing harmful effects, your blood may need to be tested often. Your kidney or liver function may also need to be tested. Visit your doctor regularly.

If you have hepatitis B you may develop liver symptoms after you stop using this medication, even months after stopping. Your doctor may want to check your liver function at regular visits for several months after you stop using rituximab. Visit your doctor regularly.

Rituximab increases the risk of a serious viral infection of the brain that can lead to disability or death. This risk is higher if you have a weak immune system or are receiving certain medicines. Call your doctor right away if you have symptoms such as change in your mental state, problems with speech or walking, or decreased vision. These symptoms may start gradually and get worse quickly.

What is rituximab?

Rituximab is a cancer medication that interferes with the growth of cancer cells and slows their growth and spread in the body.

Rituximab is used in combination with other cancer medicines to treat non-Hodgkin's lymphoma or chronic lymphocytic leukemia. Rituximab is also used in combination with another drug called methotrexate to treat symptoms of adult rheumatoid arthritis.

Rituximab is also used in combination with steroid medicines to treat certain rare disorders that cause inflammation of the blood vessels.

Rituximab may also be used for purposes not listed in this medication guide.

What should I discuss with my healthcare provider before receiving rituximab?

You should not receive this medication if you have ever had a severe allergic reaction to rituximab, or if you are allergic to mouse protein.

To make sure you can safely use rituximab, tell your doctor if you have any of these other conditions:

• liver disease or hepatitis B (or if you are a carrier of hepatitis B);
• kidney disease;
• systemic lupus erythematosus (SLE);
• lung disease or a breathing disorder;
• a weak immune system;
• a history of heart disease, angina (chest pain), or heart rhythm disorder; or
• a recent or active infection, including herpes, shingles, cytomegalovirus, chickenpox, West Nile virus, hepatitis C, or any infection that keeps coming back or does not clear up.

FDA pregnancy category C. It is not known whether rituximab will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.

It is not known whether rituximab passes into breast milk or if it could harm a nursing baby. Do not take rituximab without telling your doctor if you are breast feeding a baby.

Older adults may be more likely to have side effects from rituximab, causing breathing difficulty or heart rhythm problems.

How is rituximab given?

Rituximab is injected into a vein through an IV. You will receive this injection in a clinic or hospital setting.

Before you receive rituximab, you may be given other medications to prevent certain side effects that rituximab can cause.

The medicine is usually given once per week for 4 to 8 weeks. In the treatment of rheumatoid arthritis, you may receive only two injections of rituximab, with 2 weeks in between treatments.

To be sure this medication is not causing harmful effects, your blood may need to be tested often. Your kidney or liver function may also need to be tested. Visit your doctor regularly.

If you have hepatitis B you may develop liver symptoms after you stop using this medication, even months after stopping. Your doctor may want to check your liver function at regular visits for several months after you stop using rituximab. Do not miss any scheduled visits.

If you need surgery, tell the surgeon ahead of time that you are using rituximab.

What happens if I miss a dose?

Call your doctor if you miss an appointment for your rituximab injection.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while receiving rituximab?

Do not receive a "live" vaccine while using rituximab, and avoid coming into contact with anyone who has recently received a live vaccine. There is a chance that the virus could be passed on to you. Live vaccines include measles, mumps, rubella (MMR), Bacillus Calmette-Guérin (BCG), oral polio, rotavirus, smallpox, typhoid, yellow fever, varicella (chickenpox), H1N1 influenza, and nasal flu vaccine.

What are the possible side effects of rituximab?

Some people receiving a rituximab injection have had a reaction to the infusion (when the medicine is injected into the vein). Tell your caregiver right away if you feel dizzy, weak, nauseated, light-headed, itchy, or if you have a fever, chills, muscle pain, sneezing, sore throat, trouble breathing, or pain in your chest or shoulders. Infusion reactions often occur within the first 24 hours after the start of your rituximab infusion.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Rituximab increases the risk of a serious viral infection of the brain that can lead to disability or death. This risk is higher if you have a weak immune system or are receiving certain medicines. Call your doctor right away if you have symptoms such as change in your mental state, problems with speech or walking, or decreased vision. These symptoms may start gradually and get worse quickly.

Call your doctor at once if you have any of these other serious side effects, even if they occur several months after you receive rituximab, or after your treatment ends.

• lower back pain, blood in your urine, numbness or tingly feeling around your mouth;
• urinating less than usual;
• muscle weakness, tightness, or contraction, overactive reflexes;
• fast or slow heart rate, weak pulse, feeling short of breath, fainting;
• uneven heartbeats, wheezing or trouble breathing;
• confusion, dizziness, loss of balance, sudden numbness or weakness, especially on one side of the body;
• chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling;
• fever, chills, cough, body aches, flu symptoms, ongoing cold symptoms such as stuffy nose, sneezing, sore throat;
• easy bruising or bleeding;
• pain or burning when you urinate;
• earache, painful mouth ulcers, skin sores, warmth or swelling with skin redness;
• a red, raised, blistering, scaly, itchy, or peeling skin rash;
• severe constipation or stomach pain;
• black, bloody, or tarry stools; or
• nausea, upper stomach pain, itching, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes).

Less serious side effects may include:

• pain where the IV needle is placed;
• mild stomach pain, nausea, or diarrhea;
• swelling in your hands or feet;
• muscle or joint pain; or
• night sweats.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect rituximab?

Tell your doctor about all other medicines you use, especially:

• cisplatin (Platinol);
• adalimumab (Humira);
• auranofin (Ridaura);
• azathioprine (Imuran);
• cyclosporine (Gengraf, Neoral, Sandimmune);
• etanercept (Enbrel);
• infliximab (Remicade);
• leflunomide (Arava);
• minocycline (Dynacin, Minocin, Vectrin);
• sulfasalazine (Azulfidine);
• blood pressure medications; or
• medication to treat malaria, such as chloroquine (Aralen) or hydroxychloroquine (Plaquenil, Quineprox).

This list is not complete and other drugs may interact with rituximab. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Where can I get more information?

Your doctor or pharmacist can provide more information about rituximab.