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Ocrelizumab; Hyaluronidase Injection

What is this medication?

OCRELIZUMAB; HYALURONIDASE (ok re LIZ ue mab; hye al ur ON i dase) treats multiple sclerosis (MS). It works by slowing down an overactive immune system, which prevents or delays worsening symptoms. It also decreases the number of flare-ups. It is a monoclonal antibody.

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This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Ocrevus Zunovo

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Cancer
  • Have had hepatitis
  • Infection, especially a viral infection, such as chickenpox, cold sores, or herpes
  • Recent or upcoming vaccine
  • Stomach or intestine problems, such as colitis
  • Weakened immune system
  • An unusual or allergic reaction to ocrelizumab, hyaluronidase, other medications, foods, dyes or preservatives
  • Pregnant or trying to get pregnant
  • Breastfeeding

How should I use this medication?

This medication is injected under the skin. It is given by your care team in a hospital or clinic setting.

A special MedGuide will be given to you before each treatment. Be sure to read this information carefully each time.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

Keep appointments for follow-up doses. It is important not to miss your dose. Call your care team if you are unable to keep an appointment.

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What may interact with this medication?

Do not take this medication with any of the following:

  • Dengue vaccine

This medication may also interact with the following:

  • Medications that lower your chance of fighting infection
  • Vaccines

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Your condition will be monitored carefully while you are receiving this medication. Tell your care team if your symptoms do not start to get better or if they get worse.

You may need blood work done while you are taking this medication.

This medication can cause serious injection reactions. To reduce the risk, your care team may give you other medications to take before receiving this one. Follow the directions from your care team.

This medication may increase your risk of getting an infection. Call your care team for advice if you get a fever, chills, sore throat, or other symptoms of a cold or flu. Do not treat yourself. Try to avoid being around people who are sick.

In some patients, this medication may cause a serious brain infection that may cause death. If you have any problems seeing, thinking, speaking, walking, or standing, tell your care team right away. If you cannot reach your care team, urgently seek other source of medical care.

Talk to your care team about your vaccination history. You should not receive live vaccines while you're being treated with this medication and until your care team tells you that your immune system is no longer weakened. You may need to get some vaccines before you start treatment. If you need a non-live vaccine while you are being treated, talk to your care team.

Talk to your care team about your risk of cancer. You may be more at risk for certain types of cancer if you take this medication.

Talk to your care team if you may be pregnant. This medication has not been well studied during pregnancy. Contraception is recommended while taking this medication and for 6 months after the last dose. Your care team can help find the option that works for you.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Breast tissue changes, new lumps, redness, pain, or discharge from the nipple
  • Dizziness, loss of balance or coordination, confusion or trouble speaking
  • Infection—fever, chills, cough, sore throat, wounds that don't heal, pain or trouble when passing urine, general feeling of discomfort or being unwell
  • Injection reactions—chest pain, shortness of breath or trouble breathing, feeling faint or lightheaded
  • Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
  • Sudden or severe stomach pain, bloody diarrhea, fever, nausea, vomiting

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Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):

  • Back pain
  • Diarrhea
  • Swelling of the ankles, hands, or feet
  • Worsening mood, feelings of depression

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

This medication is given in a hospital or clinic. It will not be stored at home.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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