Ravulizumab is used to treat a certain blood disorder (paroxysmal nocturnal hemoglobinuria). This disorder causes your body's immune system to destroy red blood cells, which results in anemia. It works by helping block your body's destruction of red blood cells. This effect helps lessen symptoms of anemia (such as tiredness, shortness of breath), and may reduce the need for blood transfusions.

This medication may also be used to treat a certain immune system disorder (atypical Hemolytic Uremic Syndrome). It helps to prevent blood clots caused by this disorder.

Ravulizumab may be used to treat a certain muscle condition (generalized myasthenia gravis). It may help to improve symptoms of muscle weakness.

This medication is also used to treat a certain nervous system disorder that affects the spinal cord and eye nerve (neuromyelitis optica spectrum disorder). It may help to reduce the number of hospital stays due to the disease. Ravulizumab belongs to a class of medications known as monoclonal antibodies.

Read the Medication Guide provided by your pharmacist before you start using ravulizumab and each time you get an infusion. Carry the Patient Safety Card with you at all times during treatment and for 8 months after your last dose of ravulizumab. If you have any questions, ask your doctor or pharmacist.

This medication is given by slow injection into a vein by a health care professional as directed by your doctor. After the first dose, it is usually given 2 weeks later, then every 4 or every 8 weeks. The dosage is based on your medical condition, weight, and response to treatment.

Infusion reactions may happen during the infusion of this drug. Tell your doctor right away if you have any symptoms of infusion reactions such as low back or arm/leg pain, abdominal pain, shaking, tiredness, bad taste in mouth, drowsiness, or feeling faint. Your doctor may give you other medications to help with these side effects or may stop your treatment for some time.

Do not stop using this medication without consulting your doctor. Your condition may become worse when the drug is stopped. If you do stop using this medication, your doctor will monitor you for at least 16 weeks to make sure your condition does not get worse. Consult your doctor for more details.

Tell your doctor if your condition does not get better or if it gets worse.

See also Warning and How to Use sections.

Headache, nausea, diarrhea, dizziness, or muscle/joint pain may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor 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.

This medication may lower your ability to fight infections. This may make you more likely to get a serious (rarely fatal) infection or make any infection you have worse. Tell your doctor right away if you have any signs of infection (such as sore throat that doesn't go away, fever, chills, cough).

If you have used a similar medication recently (C5 inhibitors such as crovalimab, eculizumab), you may be at increased risk for other immune system problems. Tell your doctor right away if you have symptoms such as:

• bone pain
• numbness/tingling of the hands/feet
• unusual tiredness/weakness
• stomach/abdominal pain

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.

Before using ravulizumab, 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:

• current/recent infection

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. 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 (cannabis).

Ravulizumab can make you more likely to get certain infections (such as flu, colds, meningitis). Talk to your doctor for more details.

Tell your doctor your vaccine history and ask if you need to get any vaccines before starting treatment with this medication. Tell your health care professional that you are using ravulizumab before having any immunizations/vaccinations. 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 with your doctor.

It is unknown if this drug passes into breast milk. Because of the possible risk to the infant, breastfeeding is not recommended while using this drug and for 8 months after the last dose. Consult your doctor before breastfeeding.

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.

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 1-800-222-1222. Canada residents can call 1-844-764-7669.

Lab and/or medical tests (such as LDH levels, complete blood count) should be done while you are using this medication, and for 4 to 12 months after stopping treatment, depending on your condition. Keep all medical and lab appointments.

It is important to get each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule.

Not applicable. This medication is given in a clinic and will not be stored at home.

Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).