SIDE EFFECTS: See also Warning section. Fever, chills, dizziness, muscle stiffness, nausea, vomiting, headache, diarrhea, mild rash/itching, tiredness, flushing, or trouble breathing may occur during or after the infusion. These reactions occur more often during the first week of treatment. Tell your doctor or pharmacist right away if any of these effects occur, persist, or worsen. Your doctor may prescribe additional medications to help control these symptoms. Mouth sores, loss of appetite, shaking (tremor), stomach/abdominal pain, constipation, drowsiness, cough, increased sweating, or trouble sleeping may also occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. People using this medication may have serious side effects. However, your doctor has prescribed this drug because he or she 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: shortness of breath, mental/mood changes (such as depression, anxiety), bone/joint/back pain, muscle pain/spasm, unusual weakness, swelling ankles/feet, yellowing skin/eyes, signs of kidney problems (such as change in the amount of urine, painful urination, pink/bloody urine), numbness/tingling of arms/legs, pain/redness/swelling of arms/legs/injection site. This medication may increase your risk of getting a rare but very serious (sometimes fatal) brain infection (progressive multifocal leukoencephalopathy-PML). Get medical help right away if any of these rare but very serious side effects occur: clumsiness, loss of coordination, weakness, sudden change in your thinking (such as confusion, difficulty concentrating), difficulty moving your muscles, problems with speech, seizure, vision changes. Get medical help right away if you have any very serious side effects, including: fainting, trouble breathing, chest/jaw/left arm pain, irregular heartbeat, weakness on one side of the body, stiff neck, coma. 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 receiving this medication, tell your doctor or pharmacist if you are allergic to it; or if you have ever had a severe reaction 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: recent/current infections (such as tuberculosis), bleeding/blood problems, cancer, kidney problems, heart problems, immune system problems (e.g., HIV), thyroid problems. This drug may make you dizzy or drowsy. Alcohol or marijuana can make you more dizzy or drowsy. 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. Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). Before receiving a blood transfusion, tell your doctor that you are using this medication. Do not have immunizations/vaccinations without the consent of your doctor, and avoid contact with people who have recently received oral polio vaccine or flu vaccine inhaled through the nose. Wash your hands well to prevent the spread of infections. This medication also increases your risk of getting a very serious infection caused by a bacteria called listeria. Avoid or make sure you heat well food that may contain listeria (such as deli meat, unpasteurized milk and cheese products, soft cheeses, undercooked meat/seafood/poultry) during and for a long time after treatment with this medication. Ask your doctor for more details. To lower your risk of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports. During pregnancy, this medication should be used only when clearly needed. It may harm an unborn baby. If you become pregnant or think you may be pregnant, tell your doctor right away. Women of child-bearing age should use reliable forms of birth control (such as condoms, birth control pills) during and after treatment with this medication. Talk with your doctor for more details and to discuss the risks and benefits of treatment with this medication. It is unknown if this drug passes into breast milk. Because of the possible risk to the infant, breast-feeding is not recommended during treatment and for at least 3 to 4 months after treatment with this drug. Consult your doctor before breast-feeding.

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 include: other drugs that weaken the immune system/increase the risk of infection (such as natalizumab, rituximab).

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. Canada residents can call a provincial poison control center. Symptoms of overdose may include: trouble breathing, change in the amount of urine.