SIDE EFFECTS: See also How to Use section. Nausea, diarrhea, or trouble sleeping 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 serious side effects, including: mental/mood changes (such as new/worsening depression, thoughts of suicide), signs of cancer (such as fever, night sweats, unusual tiredness, unexplained weight loss, swollen glands, unusual lumps/growths). This medication can lower your body's ability to fight an infection. You may be more likely to get serious infections such as pneumonia, urinary tract infection, and skin infections. It may also be harder to fight an infection you already have. Tell your doctor right away if you develop signs of a serious infection while using this drug, such as: fever, chills, sore throat, cough, pain or burning with urination, urinating often, bloody diarrhea, coughing up mucus. Belimumab 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 you develop any signs of PML, including: confusion, memory loss, loss of balance, difficulty talking/walking, vision changes. Get medical help right away if you have any serious side effects, including: heart problems (such as chest/jaw/left arm pain, shortness of breath, unusual sweating, dizziness). 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 belimumab, 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: infections (current infections, infections that return), mental/mood problems (such as depression, thoughts of suicide), cancer. Belimumab can make you more likely to get infections or may worsen any current infections. Therefore, wash your hands well to prevent the spread of infection. Avoid contact with people who have infections that may spread to others (such as chickenpox, measles, flu). Consult your doctor if you have been exposed to an infection or for more details. Do not have immunizations/vaccinations without the consent of your doctor. Tell your doctor if you have had any recent immunizations. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose). Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products). During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits, and reliable forms of birth control with your doctor. The manufacturer recommends the use of reliable forms of birth control during treatment and for at least 4 months after your last treatment. It is unknown if this drug passes into breast milk. 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.