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Overview: Rituximab is used for certain cancers, rheumatoid arthritis, and certain immune conditions. The most common side effects of rituximab are nausea, infections, headaches, and feeling weak or tired. Tell your health care provider right away if you get a rash, vomiting, vision problems, or trouble walking or talking. Get emergency help if you get painful ulcers or sores, chest pain, or trouble breathing.

Uses

What is rituximab used for?

Rituximab is commonly used for the following conditions.

Rituximab may also be used for other conditions as determined by your health care provider.

How does rituximab work (mechanism of action)?

B cells are a type of white blood cell. B cells are involved in certain cancers, rheumatoid arthritis, and certain immune-related conditions. Rituximab is a monoclonal antibody that attaches to a specific protein on B cells, causing them to die. This helps to relieve symptoms of conditions involving B cells.

How is rituximab supplied (dosage forms)?

Brands and other names

  • Riabni
  • Rituxan
  • Ruxience
  • Truxima

Dosage forms and strengths

  • Rituximab is available in an injectable form that is given by a health care provider.

How should I store rituximab?

Rituximab is usually given by a health care provider in a hospital or clinic. You will not store it at home. 

Side Effects

What are the most common side effects of rituximab?

The most common side effects of rituximab are listed below. Side effects can vary based on your age and the condition being treated. Tell your health care provider if you have any of these side effects that bother you.

  • Infusion-related reactions (see below)
  • Fever/chills
  • Infections (see below)
  • Feeling unusually weak or tired 
  • Mouth sores
  • Swelling in your gut
  • Increased liver enzymes 
  • Low potassium levels
  • Nausea/diarrhea
  • Headache
  • Muscle spasms
  • Fluid retention, especially in the arms, legs, hands, and feet
  • Depression

There may be other side effects of rituximab that are not listed here. Contact your health care provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088 (800-332-1088). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of rituximab?

While less common, the most serious side effects of rituximab are described below, along with what to do if they happen.

Severe Allergic Reactions. Rituximab may cause allergic reactions, which can be serious. Stop using rituximab and get help right away if you have any of the following symptoms of a serious allergic reaction.

  • Breathing problems or wheezing
  • Racing heart
  • Fever or general ill feeling
  • Swollen lymph nodes
  • Swelling of the face, lips, mouth, tongue, or throat
  • Trouble swallowing or throat tightness
  • Itching, skin rash, or pale red bumps on the skin called hives
  • Nausea or vomiting
  • Dizziness, feeling lightheaded, or fainting
  • Stomach cramps
  • Joint pain

Infusion-related Reactions. Rituximab can cause reactions that can be serious when it is given to you. Your health care provider may have you take other medicines before each dose of rituximab to lower your risk of having an infusion reaction. Your infusion may need to be slowed or stopped if you have these reactions. Tell your health care provider right away (or get emergency help) if you have any of the following symptoms when you get your infusion or in the day afterward. 

  • Itching, skin rash, or pale red bumps on the skin called hives
  • Low blood pressure
  • Swelling of the face, lips, mouth, tongue, or throat (angioedema)
  • Coughing, trouble breathing, or wheezing
  • Weakness
  • Confusion, dizziness, or feeling like you might pass out
  • Chest pain
  • Feeling like your heart is racing 

Severe Skin Reactions. Rituximab can cause severe skin reactions, called Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN), that can lead to death if not treated. If you get a rash, stop rituximab and call your health care provider right away. Get emergency help if you have any of the following symptoms of SJS or TEN.

  • Painful red or purple skin that looks burned and peels off
  • Flat red rash or blisters on your skin, lips, mouth, nose, and genitals
  • Red, painful, watery eyes
  • Pus-filled pimples

Hepatitis B Virus Reactivation. If you have the hepatitis B virus in your body or have had hepatitis B in the past, rituximab could make the virus active again. Keep all appointments for bloodwork before starting rituximab and during treatment. Call your health care provider right away if you have any of the following symptoms of hepatitis.

  • Unusual tiredness
  • Your skin or the whites of your eyes turning yellowish in color (also called jaundice)
  • Nausea, vomiting, or loss of appetite
  • Dark-colored pee
  • Fever or chills
  • Pain in your side
  • Stool (poop) that is clay-colored

Progressive Multifocal Leukoencephalopathy (PML). People using rituximab may get a rare brain disease called PML. It is caused by a virus called the JC virus. PML is very serious and can lead to death. Stop using rituximab and call your health care provider right away if you have any of the following symptoms of PML.

  • Clumsiness or loss of coordination
  • A hard time walking or speaking
  • Facial drooping
  • Vision problems
  • Thinking, memory, or personality changes
  • Weakness on one side of your body that gets worse
  • Seizures

Tumor Lysis Syndrome. Rituximab can cause a fast breakdown of cancer cells. This can lead to a condition called tumor lysis syndrome, which can be serious. It can damage your kidneys and cause you to have an abnormal heartbeat. It is important to drink plenty of water while receiving rituximab and to keep all of your appointments for bloodwork so your health care provider can see how your body is responding to rituximab. Tell your health care provider right away if you have any of the following signs of tumor lysis syndrome while using rituximab. 

  • Nausea, vomiting, or diarrhea
  • Weakness or feeling like you have no energy
  • Swelling or fluid retention
  • Shortness of breath
  • Muscle cramps
  • Seizures

Infections. Rituximab can increase your risk of infections, including serious infections. Call your health care provider right away if you have an infection or any of the following symptoms.

  • Burning or stinging when you pee 
  • Common cold symptoms that will not go away
  • Cold sores
  • White patches in your mouth or throat
  • Headache or ear pain
  • Flu-like symptoms, such as coughing and feeling achy or tired
  • Coughing, or coughing up blood
  • Fever, sweats, chills, or muscle aches
  • Shortness of breath
  • Diarrhea or stomach pain
  • Weight loss
  • Cuts, scrapes, or breaks in your skin that are red, painful, warm to the touch, or swollen

Heart Effects. Rituximab may increase your risk of certain effects on the heart, such as an abnormal heart rhythm, a heart attack, or cardiogenic shock (when the heart cannot pump enough blood and oxygen to your organs). Get emergency help if you have any of the following symptoms.

  • Confusion
  • Chest pain or pressure
  • Fast or abnormal heartbeat
  • Trouble breathing
  • Pain in your back, jaw, throat, or arm
  • Sweating, upset stomach, vomiting, or dizziness

Kidney Damage. Kidney damage can happen when using rituximab. Keep all appointments for lab work while using rituximab. Stop using rituximab and call your health care provider right away if you have any of the following symptoms of kidney damage.

  • Reduced need to pee
  • Swelling in your feet, ankles, or legs
  • Weakness or unusual tiredness
  • A hard catching your breath or chest pain/pressure
  • Confusion
  • Nausea
  • Seizures

Gut Blockage or Tear. Rituximab can cause a blockage or tear in the intestines, especially if it is used with other medicines, such as chemotherapy. Call your health care provider right away if you have any of the following symptoms.

  • Vomiting over and over
  • Severe stomach pain
  • Blood in your stool (poop)

Warnings & Precautions

Who should not use rituximab?

Allergies to Ingredients. People who are allergic to any of the following should not use rituximab.

  • Rituximab
  • Riabni
  • Rituxan
  • Ruxience
  • Truxima
  • Any of the ingredients in the specific product dispensed

Your pharmacist can tell you all of the ingredients in the specific rituximab products they stock.

What should I know about rituximab before using it?

Rituximab is an intravenous (IV) infusion that you will get at a hospital or clinic. You may get other medicines before rituximab to reduce your risk of having fever and chills with rituximab. 

People who are 65 or older can be at greater risk of some side effects of rituximab. Talk to your health care provider about your risks if you are in this age group.

You may need to take medicine(s) to prevent infections for up to 12 months after using rituximab. Talk to your health care provider if you have any concerns or questions. 

What should I tell my health care provider before using rituximab?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know if rituximab is right for you.

In particular, make sure that you discuss any of the following.

Vaccines. Talk with your health care provider about any vaccines that you may need. You should not receive certain vaccines right before or while using rituximab. Tell your health care provider about any vaccines you have recently received or have scheduled.

Risk of Infection. Before starting rituximab, it is important to talk to your health care provider about any serious infections you have had in the past, as well as any current infections. Also, tell your health care provider if you have an infection that keeps coming back. Some examples of serious infections that you should mention to your health care provider include hepatitis B or C, cytomegalovirus (CMV), herpes, parvovirus B19, chickenpox, shingles, or West Nile virus.

Current and Past Health Conditions. Tell your health care provider if you have any of the following.

  • Had a reaction to any rituximab product in the past
  • Heart problems, including an irregular heart beat or chest pain
  • Lung problems
  • Kidney problems
  • Current infection or a weak immune system

Other Medicines and Supplements. Rituximab may interact with other medicines and supplements. Before using rituximab, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. Rituximab may harm an unborn baby. Tell your health care provider right away if you are pregnant, think you are pregnant, or plan to become pregnant. You may need a negative pregnancy test before you can get rituximab. Use effective birth control while using rituximab and for one year after your last dose. If you become pregnant while taking rituximab, your health care provider may monitor your child for side effects after birth.

Breastfeeding. Do not breastfeed while using rituximab or for six months after your last dose. Rituximab may pass into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.

Interactions

Does rituximab interact with foods or drinks?

There are no known interactions between rituximab and foods or drinks.

It is unknown if drinking alcohol will affect rituximab.

Does rituximab interact with other medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before using rituximab.

  • Cisplatin, which is a medicine used for certain cancers
  • A disease modifying antirheumatic drug (DMARD), such as hydroxychloroquine (Plaquenil, Sovuna) or leflunomide (Arava), that is a medicine that is commonly used for rheumatoid arthritis
  • A tumor necrosis factor (TNF) blocker, such as adalimumab (Humira, others), etanercept (Enbrel, others), or infliximab (Remicade, others), which is a medicine that is commonly used for rheumatoid arthritis and certain skin conditions

This may not be a complete list of medicines that can interact with rituximab. Always check with your health care provider.

Does interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker

Overdose/Missed Dose

What should I do if I accidentally use too much rituximab?

If you or someone else has used too much rituximab, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

What should I do if I miss a dose of rituximab?

Rituximab is usually given by a health care provider in a hospital. Your health care provider will make sure you are receiving rituximab as scheduled.

If you miss an appointment to get your rituximab dose, call to make another appointment as soon as possible. 

 

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