SIDE EFFECTS: Headache, joint pain, redness/irritation at the injection site, swelling hands/feet/ankles, or changes in menstrual cycle may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects. Tell your doctor right away if you have any side effects while this drug is being given or shortly after your treatment is finished. Examples of these side effects (infusion reaction) may include chills, fever, flushing, nausea, dizziness, tiredness, and chest pain. Tell your doctor right away if any of these unlikely but serious side effects occur: severe/persistent headache, stiff/painful neck, fast/pounding heartbeat, signs of infection (such as fever, persistent sore throat, breathing problems, unusual vaginal discharge, painful/frequent urination), mood changes (such as depression, suicidal thoughts), severe stomach/abdominal pain. This drug increases the risk of a rare, possibly fatal, brain infection (see Warning section for more details). This condition may occur during treatment or, in some cases, after treatment has stopped. In MS patients, the symptoms of PML can seem like an attack of worsening MS. Therefore, whether you are using this drug or have stopped using it within the last 6 months, tell your doctor right away of any new or worsening symptoms that have lasted for several days such as: clumsiness, sudden change in your thinking (such as confusion, difficulty concentrating), difficulty moving muscles, seizure, problems with speech, vision changes. This drug may rarely cause serious liver problems. If you notice any of the following rare but very serious side effects, tell your doctor right away: persistent nausea/vomiting, dark urine, yellowing eyes/skin, feeling tired/weak. A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any of the following symptoms: 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 this medication, 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. This medication should not be used if you have ever had a certain medical condition. Before using this medicine, consult your doctor or pharmacist if you have ever had: a certain virus infection (progressive multifocal leukoencephalopathy-PML). Before using this medication, tell your doctor or pharmacist your medical history, especially of: weakened immune system (such as leukemia, lymphoma, HIV infection, organ transplant), current infections, history of certain virus infections that keep coming back (such as herpes, shingles), mental/mood disorders (such as depression). During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. It is not known if this drug passes into breast milk. Because of the possible risk to the infant, breast-feeding is not recommended while using 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: past or current use of other drugs that weaken the immune system/increase the risk of infection (such as azathioprine, cyclosporine, 6-mercaptopurine, methotrexate, fingolimod, TNF blockers such as adalimumab, etanercept, infliximab), long-term use of corticosteroids (such as dexamethasone, prednisone).

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.