Uses

Rituximab is used to treat certain types of cancer (such as non-Hodgkin's lymphoma, chronic lymphocytic leukemia). Rituximab belongs to a class of drugs known as monoclonal antibodies. It works by slowing or stopping the growth of cancer cells.

How To Use

Read the Medication Guide provided by your pharmacist before you start using rituximab and each time you get a refill. If you have any questions, ask your doctor or pharmacist.

Your doctor will prescribe other medications (such as acetaminophen, an antihistamine, methylprednisolone) for you to take before each treatment to help reduce side effects, such as fever and chills. Carefully follow your doctor's instructions.

This medication is given by injection under the skin of your abdomen by a health care professional. It is given as directed by your doctor, usually over 5 to 7 minutes. This form of rituximab is used only after receiving your first dose of rituximab by injection into a vein. The dosage and treatment schedule are based on your medical condition, other medications you may be taking, and response to treatment.

Ask your doctor if you should take your regular medications (such as drugs for high blood pressure) before your treatment.

Side Effects

See also Warning section.

Pain, swelling, bruising, redness, or itching at the injection site may occur. Headache, nausea, weakness, or dizziness may also 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:

• abdominal pain
• increased thirst/urination
• swelling of the hands/feet
• tingling of the hands/feet

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 bleeding problems and lower your ability to fight infections. This may make you more likely to get a serious (rarely fatal) infection or make any infection you have worse. Tell your doctor right away if you develop any of the following side effects: 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, cough).

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.

Precautions

Before using rituximab, tell your doctor or pharmacist if you are allergic to it; 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:

• bleeding/blood problems
• heart problems (such as irregular heartbeat, previous heart attack)
• current/recent infections
• lung problems
• stroke

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).

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.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

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.

Drug Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug are:

• other drugs that weaken the immune system/increase the risk of infection (such as natalizumab, fingolimod, tofacitinib)

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center.

Notes

Lab and/or medical tests (such as blood counts, hepatitis B virus, kidney/liver function) should be done before you start using this medication and while you are using it. Keep all medical and lab appointments.

Missed Dose

It is important to get each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule.

If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.

Storage

Not applicable. This medication is given in a hospital or clinic or doctor's office and will not be stored at home.

Medical Alert

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).