Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).
Rituximab may rarely cause serious (sometimes fatal) side effects including severe breathing problems or heart problems (such as heart attack, irregular heartbeat). If these serious side effects occur, they usually happen during the first treatment with rituximab. Your doctor will carefully watch you during treatment and may stop or slow down your treatment if you have any signs of a reaction. Get medical help right away if you have trouble breathing, itching, swelling (especially of the throat/lips), dizziness, fast/slow/irregular heartbeat, or chest pain.
Rarely, people using this medication have had serious (sometimes fatal) skin reactions (such as Stevens-Johnson syndrome). Get medical help right away if you develop any rash, blisters, peeling skin, or sores on your skin, lips, or in your mouth.
This medication may increase your risk of getting a rare but very serious (possibly fatal) brain infection (progressive multifocal leukoencephalopathy-PML). Get medical help right away if you have any of these side effects: clumsiness, loss of coordination/balance, weakness, sudden change in your thinking (such as confusion, difficulty concentrating, memory loss), difficulty talking/walking, seizure, vision changes.
Rituximab may cause serious (possibly fatal) liver disease in people who have a current or past infection with hepatitis B. This may occur during treatment or up to 2 years after treatment is finished. Before starting this medication, tell your doctor if you have ever had hepatitis B. Your doctor should order a test to see if you have the hepatitis B infection before starting treatment. Tell your doctor right away if you have symptoms of liver disease, such as nausea/vomiting that doesn't stop, loss of appetite, stomach/abdominal pain, yellowing eyes/skin, or dark urine.
Before using rituximab, tell your doctor or pharmacist if you are allergic to it; or to any rituximab products; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: lung disease, heart problems (such as irregular heartbeat, previous heart attack), bleeding/blood disorders, current/recent infections.
This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Rituximab can make you more likely to get infections or may make current infections worse. Stay away from anyone who has an infection that may easily spread (such as chickenpox, COVID-19, measles, flu). Talk to your doctor if you have been exposed to an infection or for more details.
Tell your health care professional that you are using rituximab before having any immunizations/vaccinations. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose).
To lower the chance of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.
Older adults may be at greater risk for heart problems (such as irregular heartbeat) or lung problems while using this drug.
Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using rituximab. Rituximab may harm an unborn baby. Your doctor should order a pregnancy test before you start this medication. Ask about reliable forms of birth control while using this medication and for 1 year after the last dose. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.
This drug passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this drug and for at least 6 months after the last dose. Consult your doctor before breastfeeding.
See also Warning section.
Nausea, vomiting, headache, dizziness, joint/muscle pain, weakness, or flushing may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
People using this medication may have serious side effects. However, you have been prescribed this drug because your doctor has judged that the benefit to you is greater than the risk of side effects. Careful monitoring by your doctor may decrease your risk.
Tell your doctor right away if you have any serious side effects, including: signs of stomach/intestinal blockage (such as constipation, stomach/abdominal pain), swelling hands/ankles/feet, increased thirst/urination, numbness/tingling of arms/legs.
Rituximab sometimes causes side effects due to the rapid destruction of cancer cells (tumor lysis syndrome). To lower your risk, your doctor may add a medication and tell you to drink plenty of fluids. Tell your doctor right away if you have symptoms such as: low back/side pain (flank pain), signs of kidney problems (such as painful urination, pink/bloody urine, change in the amount of urine), muscle spasms/weakness.
This medication can decrease blood cells, which can cause anemia, decrease your body's ability to fight an infection, or cause easy bruising/bleeding. Tell your doctor right away if you develop any of the following symptoms: easy bleeding/bruising, black/tarry stools, vomit that looks like coffee grounds, signs of an infection (such as sore throat that doesn't go away, fever, chills), unusual tiredness, pale skin.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
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