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Siltuximab

Brand names: Sylvant

What is siltuximab used for?

  • Siltuximab is used to treat multicentric Castleman's Disease (MCD).

Before taking siltuximab, tell your doctor:

  • If you are allergic to siltuximab; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
  • If you have an infection.

This is not a list of all drugs or health problems that interact with siltuximab.

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 siltuximab with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take siltuximab?

  • Tell all of your health care providers that you take siltuximab. This includes your doctors, nurses, pharmacists, and dentists.
  • You may have more chance of getting an infection. Wash hands often. Stay away from people with infections, colds, or flu.
  • Talk with your doctor before getting any vaccines. Use of some vaccines with siltuximab may either raise the chance of an infection or make the vaccine not work as well.
  • Holes in the GI (gastrointestinal) tract may rarely happen.
  • High triglyceride levels have happened with siltuximab. Tell your doctor if you have ever had high triglyceride levels.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • Some patients have very bad side effects during the infusion. Tell your doctor if you have any bad effects during the infusion.
  • Watch for gout attacks.
  • Birth control pills and other hormone-based birth control may not work as well to prevent pregnancy. Use some other kind of birth control also like a condom when taking siltuximab.
  • Women must use birth control while taking siltuximab 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 siltuximab 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.

How is siltuximab best taken?

Use siltuximab 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.

What do I do if I miss a dose?

  • Call your doctor to find out what to do.

What are the side effects of siltuximab that I need to call my doctor about immediately?

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 kidney problems like unable to pass urine, change in how much urine is passed, blood in the urine, or a big weight gain.
  • Dizziness or passing out.
  • Very bad belly pain.
  • Upset stomach or throwing up.
  • Back pain.
  • Chest pain.
  • A heartbeat that does not feel normal.
  • Flushing.
  • Swelling.
  • Any unexplained bruising or bleeding.

What are some other side effects of siltuximab?

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:

  • Constipation.
  • Headache.
  • Throat pain.
  • Weight gain.
  • Signs of a common cold.

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 the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

If overdose is suspected:

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.

How do I store and/or throw out siltuximab?

  • If you need to store siltuximab at home, talk with your doctor, nurse, or pharmacist about how to store it.

Consumer information use and disclaimer

  • 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. Check with your pharmacist. If you have any questions about siltuximab, please talk with your doctor, nurse, 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.

This information should not be used to decide whether or not to take siltuximab or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to siltuximab. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.

Source: Wolters Kluwer Health. Last updated April 5, 2023.