This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
- It is used to treat MS (multiple sclerosis).
- If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have an infection.
- If you have active hepatitis B infection.
This is not a list of all drugs or health problems that interact with this drug.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- If you have had hepatitis B before or carry the virus, this drug can cause the virus to become active. This can lead to very bad and sometimes deadly liver problems. You will be tested for hepatitis B before starting this drug. You will need to watch for signs of hepatitis while taking this drug and for several months after stopping it. Talk with your doctor.
- Talk with your doctor before getting any vaccines. Use of some vaccines with this drug may either raise the chance of an infection or make the vaccine not work as well.
- Make sure you are up to date with all your vaccines before treatment with this drug. Talk with your doctor to find out when you need to get any vaccines before starting this drug.
- You may have more chance of getting an infection. Wash hands often. Stay away from people with infections, colds, or flu.
- Severe infections caused by certain viruses have happened with this drug. Sometimes, these were life-threatening. If you have questions, talk with the doctor.
- This drug may lower the number of a type of antibody (immunoglobulin) in your blood. Low levels of these antibodies may raise the risk of severe infections. Blood tests will be done before you start taking this drug and while you take it to check the level of these antibodies.
- This drug may add to the chance of getting some types of cancer. Talk with the doctor.
- Be sure to have regular breast exams. Your doctor will tell you how often to have these. You will also need to do breast self-exams as your doctor has told you. Talk with your doctor.
- If you may become pregnant, you must use birth control while taking this drug and for some time after the last dose. Ask your doctor how long to use birth control. If you get pregnant, call your doctor right away.
- If you used this drug when you were pregnant, tell your baby’s doctor.
- Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of infection like fever, chills, very bad sore throat, ear or sinus pain, cough, more sputum or change in color of sputum, pain with passing urine, mouth sores, or wound that will not heal.
- Signs of skin infection like oozing, heat, swelling, redness, or pain.
- Signs of herpes infections like cold sores, shingles, genital sores, severe headache, confusion, change in eyesight, eye redness, or eye pain.
- A lump in the breast or breast soreness.
- Swelling in the arms or legs.
- Low mood (depression).
- Reactions have happened during the infusion and within 24 hours after the infusion. Sometimes, infusion reactions have been life-threatening. Tell your doctor right away if you have rash, hives, itching, fever, fast heartbeat, shortness of breath or trouble breathing, dizziness or passing out, upset stomach, throat irritation or pain, headache, feeling tired, swelling of the throat, coughing or wheezing, or flushing during or within 24 hours after the infusion.
- A very bad brain problem called progressive multifocal leukoencephalopathy (PML) may happen with this drug. It may cause disability or can be deadly. Tell your doctor right away if you have signs like confusion, memory problems, low mood (depression), change in the way you act, change in strength on 1 side is greater than the other, trouble speaking or thinking, change in balance, or change in eyesight.
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Signs of a common cold.
- Back pain.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- It is given as an infusion into a vein over a period of time.
- Other drugs may be given to help with infusion side effects.
- Call your doctor to find out what to do.
- If you need to store this drug at home, talk with your doctor, nurse, or pharmacist about how to store it.
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else’s drugs.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- This drug comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time this drug is refilled. If you have any questions about this drug, please talk with the doctor, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
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