Rystiggo (rozanolixizumab-noli) can cause side effects that range from mild to serious. More common side effects include headache and infection. If side effects become difficult to tolerate, talk with your doctor about other treatment options.

Rystiggo is used in certain adults to treat generalized myasthenia gravis.

Keep reading to learn about the common, mild, and serious side effects Rystiggo can cause. To learn more about this drug, including its uses, dosage, and cost, read this Rystiggo overview.

Rystiggo can cause certain side effects, some more common than others. These side effects may be temporary, lasting a few days to weeks. Talk with your doctor if side effects do not go away, get worse, or become too difficult for you to manage.

Rystiggo’s commonly reported side effects include:

  • headache
  • infection (see “Side effects specifics”)
  • fever
  • diarrhea
  • nausea

Mild side effects have been reported with Rystiggo. These include:

In most cases, these side effects should be temporary, and some may be easily managed. But if you have symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. Do not stop Rystiggo treatment unless your doctor recommends it.

Rystiggo may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

For more information about some of these side effects, see the “Side effects specifics” section.

Rystiggo may cause serious side effects. The following list may not include all possible serious side effects of the drug. For more information, you can refer to Rystiggo’s prescribing information.

If you develop serious side effects during Rystiggo treatment, 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.

Serious side effects that have been reported with this medication include:

For more information about some of these side effects, see the “Side effects specifics” section.

Allergic reaction

For some people, Rystiggo can cause an allergic reaction.

In general, symptoms of an 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 Rystiggo treatment.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty 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 Rystiggo, they may have you switch to a different treatment.

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

Infection

Infection was a common side effect reported in studies of Rystiggo. Most infections were mild, but some were serious.

Note: While the drug itself does not cause infection, it can weaken your immune system, making you more susceptible to infection.

Examples of infections reported in people receiving Rystiggo include:

An infection may cause symptoms such as:

Factors that can increase the risk of infection during Rystiggo treatment include getting live vaccinations. (Live vaccines contain a weakened form of the bacteria or virus that the vaccine is used to help prevent.)

What you can do

If you have symptoms of an infection during Rystiggo treatment, talk with your doctor or pharmacist. If the infection is mild, they may recommend over-the-counter (OTC) options to help relieve your symptoms. These may include:

For some infections, such as a UTI or more serious infection, a pharmacist will likely recommend seeing your doctor. Your doctor may prescribe medication to treat the infection. In this case, they may also recommend delaying your next dose of Rystiggo until after the infection has cleared up.

Infusion site reaction

Rystiggo comes as a liquid solution that’s given as an infusion under your skin by a healthcare professional. (An infusion is a type of injection given over a period of time.) You’ll receive Rystiggo infusions in your lower abdomen, below your belly button.

Infusion site reactions were a common and typically mild side effect reported in Rystiggo studies.

Infusion reactions may cause symptoms at or near the site of the injection such as:

Factors that increase the risk of infusion site reactions with Rystiggo include having the infusion in the same site each time. The infusion should be administered in a different site each time you receive a dose, avoiding areas that are tender, bruised, hard, or discolored.

What you can do

If you have a bothersome infusion site reaction after receiving Rystiggo, it may help to apply a cold pack to the area. To ease pain, you could also take an OTC pain reliever such as acetaminophen (Tylenol). To help relieve itching, you could take an antihistamine. Ask your pharmacist to recommend a product that’s right for you.

If you have a reaction that’s severe or doesn’t get better after a few days, talk with your doctor or pharmacist.

Aseptic meningitis

Aseptic meningitis was a rare side effect reported in studies of Rystiggo.

Aseptic meningitis is a condition that causes swelling around the brain and spinal cord. It may cause symptoms such as:

  • severe headache
  • sensitivity to light
  • fever
  • nausea and vomiting
  • neck stiffness

What you can do

If you have symptoms of aseptic meningitis, see your doctor right away. They’ll likely order tests to try and determine the cause of your symptoms and will recommend the best way to treat them.

If you have aseptic meningitis, your doctor will likely recommend that you stop Rystiggo treatment. Your symptoms will usually get better in a few days. In the meantime, your doctor will likely recommend that you rest and drink plenty of water. They may also recommend taking OTC drugs like acetaminophen (Tylenol) to help relieve pain and reduce fever.

Before starting Rystiggo treatment, discuss your health history with your doctor. This medication may not be right for you if you have certain medical conditions or other factors affecting your health.

Be sure to tell your doctor if any of the following apply to you:

  • current infection or history of infections
  • previous allergic reaction to this or a similar drug
  • pregnancy
  • breastfeeding
  • alcohol consumption
  • recent or upcoming vaccinations

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.