Ultomiris (ravulizumab-cwvz) is a prescription drug used to treat certain rare inflammatory conditions. Ultomiris can cause side effects that range from mild to serious. Examples include headache, upper respiratory infection, and diarrhea.

Ultomiris is a prescription medication that’s used to treat the following conditions:

Keep reading to learn about the common, mild, and serious side effects that Ultomiris infusions can cause. And for a detailed overview of this drug, check out this in-depth Ultomiris article.

Ultomiris has a boxed warning. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Boxed warning for Ultomiris” section.

Here are some of the more common side effects reported by people who received Ultomiris in studies. These side effects can vary depending on the condition the drug is being used to treat.

More common side effects in people receiving Ultomiris for aHUS include:

* To learn more about this side effect, see the “Side effects specifics” section.

More common side effects in people receiving Ultomiris for PNH include:

  • headache
  • upper respiratory tract infection

More common side effects in people receiving Ultomiris for gMG include:

  • upper respiratory tract infection
  • diarrhea

More common side effects in people receiving Ultomiris for NMOSD include:

Mild side effects have been reported with Ultomiris. These side effects varied depending on the condition Ultomiris was used to treat. Mild side effects include:

In most cases, these side effects should be temporary. And some may be easily managed, too. But if you have any symptoms that are ongoing or bother you, talk with your doctor.

Ultomiris may cause mild side effects other than the ones listed. See the drug’s prescribing information for details.

* To learn more about this side effect, see the “Side effects specifics” section.

Some people have experienced serious side effects while receiving Ultomiris in studies, though this was rare.

Serious side effects that have been reported with Ultomiris include:

If you develop serious side effects while receiving Ultomiris, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Note: After the FDA approves a drug, it tracks side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Ultomiris, visit MedWatch.

* To learn more about this side effect, see the “Side effects specifics” section.
† For details about this side effect, see “Boxed warning for Ultomiris.”

Allergic reaction

For some people, Ultomiris can cause an allergic reaction but these reactions were rare in studies of the drug.

In general, symptoms of allergic reaction can be mild or serious.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should continue Ultomiris treatment.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Ultomiris, they may have you switch to a different treatment.

Ultomiris has a boxed warning for the risk of serious meningococcal infections. A boxed warning is the most serious warning from the FDA.

Meningococcal infections are caused by a certain kind of bacteria and can be severe. In fact, life threatening infections of this kind occurred in studies of Ultomiris.

Meningococcal infections usually occur in the lining of the brain and spinal cord. They can also spread throughout the body and cause sepsis, which is a severe response to an infection that can become fatal.

Some of the symptoms of meningococcal infections or sepsis include:

What you can do

If your meningococcal vaccinations are not up to date, your doctor will recommend that you get these immunizations at least 2 weeks before starting Ultomiris treatment. Doctors usually will not prescribe Ultomiris to people who haven’t received meningococcal vaccines. Vaccination reduces your risk of getting a meningococcal infection, though it’s still possible.

Due to the risk of meningococcal infection, Ultomiris is only available through a risk evaluation and mitigation strategy (REMS). The REMS is designed to help prevent anyone who uses Ultomiris from getting this kind of infection. As part of this program, only healthcare professionals who are specially certified may prescribe Ultomiris.

For more information about the Ultomiris REMS, talk with your doctor or visit the Ultomiris REMS webpage.

In addition, your doctor will monitor you closely for symptoms of meningococcal infection. If you’re experiencing symptoms of meningococcal infection or sepsis, contact your doctor right away. If any of the symptoms seem life threatening, call 911 or seek emergency medical care immediately.

Learn more about some of the side effects Ultomiris may cause.

High blood pressure

In studies, high blood pressure was a common serious side effect in people receiving Ultomiris to treat aHUS.

High blood pressure rarely causes symptoms. But in extreme cases of severe high blood pressure, you may notice symptoms such as:

There were no reports of severe high blood pressure that caused symptoms in studies of Ultomiris.

What you can do

If you have any concerns about high blood pressure during Ultomiris treatment, talk with your doctor. They may monitor your blood pressure more often during treatment and have you do the same at home. Your doctor may also prescribe medications to help lower your blood pressure.

If you notice symptoms of severe high blood pressure as described, immediately seek medical attention at the closest emergency room or dial 911.

Anxiety

Some people reported anxiety during Ultomiris studies for aHUS. But it’s unknown whether this side effect was caused by Ultomiris.

Symptoms of anxiety may include:

What you can do

To help ease anxiety during Ultomiris treatment, there are a few things you can try at home: taking a warm bath, meditating, listening to calming music, or doing anything that makes you feel calm and safe.

If your anxiety doesn’t lessen or becomes bothersome, talk with your doctor. They can recommend therapy or other medications to help manage this side effect.

Serious infections

In studies of Ultomiris, some people developed serious infections, such as pneumonia or tonsillitis. Children may have an increased risk of developing certain infections while receiving Ultomiris.

Symptoms of an infection may include:

What you can do

Make sure you or your child are up to date on vaccinations. Before starting treatment with Ultomiris, ask your doctor about any vaccinations that you may need.

If you develop any symptoms of an infection, contact your doctor right away. They’ll likely want to see you in person to determine the type and severity of your infection. Then they can recommend an appropriate treatment based on your infection.

Keeping track of side effects

During your Ultomiris treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were receiving when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how it affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Keeping notes and sharing them with your doctor will help them learn more about how Ultomiris affects you. They can then use this information to adjust your treatment plan if needed.

Get answers to some frequently asked questions about the side effects of Ultomiris.

Can Ultomiris cause mood changes, such as anger?

In general, it’s not likely. For example, anger was not reported in studies of Ultomiris.

But anxiety was reported by some people receiving Ultomiris to treat aHUS. (You can learn more about this side effect in the “Side effects specifics” section.)

If you’re experiencing mood changes during Ultomiris treatment, talk with your doctor.

Does Ultomiris cause brain-related side effects?

Yes, Ultomiris may cause certain brain-related side effects. In studies of the drug, some people experienced dizziness and headache.

Others developed meningococcal infection, a more serious and sometimes life threatening side effect involving the brain or spinal cord. In fact, Ultomiris has a boxed warning for the risk of this side effect. (For more information, see the “Boxed warning for Ultomiris” section.)

If you have questions about brain-related side effects that Ultomiris might cause, talk with your doctor.

Will I have side effects after suddenly stopping Ultomiris treatment?

It’s possible. If you’re receiving the drug for PNH, your doctor will monitor you for hemolysis (ruptured red blood cells) for 16 weeks after you stop receiving Ultomiris. If you’re receiving the drug for aHUS, they’ll monitor you for signs and symptoms of thrombotic microangiopathies, such as destruction of red blood cells, low platelet level, and organ damage, for 12 months.

You could also develop a meningococcal infection up to several months after stopping Ultomiris treatment. (This is a serious side effect of Ultomiris. See the “Boxed warning for Ultomiris” section for details.)

If you’re considering ending Ultomiris treatment, talk with your doctor about how they’ll do so safely and what to expect.

What Ultomiris side effects might a baby have?

Ultomiris is approved to treat PNH or aHUS in children 1 month and older.

In studies of Ultomiris, children and adults experienced similar side effects. The most common side effects that occurred in children were upper respiratory tract infections, abdominal pain, low levels of red blood cells, and headache.

Children also have a risk of meningococcal infections when receiving Ultomiris. Babies may experience different symptoms for this condition than older children and adults, including:

If your baby has any of these symptoms during Ultomiris treatment, contact their doctor right away.

For more information about side effects babies and children of different ages may have from Ultomiris, talk with their doctor.

Consider the following important information before starting Ultomiris.

Ultomiris has a boxed warning. A boxed warning is the most serious warning from the FDA. For details, see the “Boxed warning for Ultomiris” section.

Other warnings

Ultomiris may not be right for you if you have certain medical conditions. These are known as drug-condition interactions. Other factors may also affect whether Ultomiris is a good treatment option for you.

Talk with your doctor about your health history before starting Ultomiris. The following list includes factors to consider:

  • active infection, including meningococcal infection
  • previous allergic reaction to Ultomiris
  • pregnancy
  • breastfeeding
  • alcohol consumption

Q:

Do I need to take antibiotics if I have not been vaccinated against meningococcal infections?

Anonymous

A:

If your meningococcal vaccinations are not up to date, your doctor will recommend that you receive the appropriate vaccines before you start Ultomiris treatment.

If you are vaccinated less than 2 weeks before starting Ultomiris treatment, you’ll likely need to take antibiotics for 2 weeks. The antibiotics help to prevent meningococcal infections before the vaccine starts working.

This is important because Ultomiris has a risk of meningococcal infections, which may lead to sepsis. In fact, Ultomiris has a boxed warning for this risk. A boxed warning is the most serious warning from the FDA. (For more information about this warning, see the “Boxed warning for Ultomiris” section.)

Due to this risk, your doctor will not prescribe Ultomiris if you have a current meningococcal infection of if you haven’t been vaccinated against this kind of infection.

You may still get an infection if you take antibiotics and are vaccinated against meningococcal infections.

If you have any questions about Ultomiris and vaccinations, meningococcal infections, or antibiotics, ask your doctor.

The Healthline Pharmacist TeamAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.