Spinraza (nusinersen) is a prescription drug used to treat spinal muscular atrophy. Spinraza can cause side effects that range from mild to serious. Examples include headache and fever.

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

Some people may experience mild to serious side effects during Spinraza treatment. Examples of the drug’s commonly reported side effects include:

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

Mild side effects have been reported with Spinraza. 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.

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

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

Serious side effects have been reported with Spinraza. These include:

If you develop serious side effects during Spinraza 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.

* To learn more about this side effect, see the “Side effects explained” section.
† Hydrocephalus and post-lumbar puncture infections weren’t reported in the drug’s studies but have been reported since the drug became available for use.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Spinraza, visit MedWatch.

ALLERGIC REACTION

For some people, Spinraza can cause an allergic reaction.

Allergic reaction was not reported in the drug’s studies but has been reported since the drug became available for use.

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 Spinraza 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 Spinraza, they may have you switch to a different treatment.

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

Back pain

Back pain was a common but mild side effect reported in Spinraza studies and may cause symptoms like:

  • dull aching sensation in the lower back
  • difficulty standing up straight without pain
  • a stabbing or shooting pain that can radiate down the leg to the foot
  • numbness, tingling, or weakness in one or both legs

What might help

If you have mild back pain during Spinraza treatment, talk with your doctor. They’ll likely recommend stretching, gentle exercises, ice packs, or warm compresses to help relieve your pain. In some cases, they may recommend an over-the-counter pain medication such as acetaminophen (Tylenol) or ibuprofen to relieve mild, temporary pain.

If your back pain is serious, bothersome, or ongoing, call your doctor. They can diagnose the cause and suggest options for you to consider. This may include stopping Spinraza and switching to a different medication.

Kidney problems

Treatment with Spinraza may increase your risk of kidney problems. This was a serious side effect reported in the drug’s studies.

Symptoms of kidney problems may include:

What might help

Before you begin treatment with Spinraza, your doctor will order tests to check your kidney function. They’ll also monitor your kidney function during treatment.

If you have symptoms of kidney problems, call your doctor right away. But if you feel you’re having a medical emergency, call 911 or your local emergency number immediately.

Talk with your doctor if you have questions about this side effect of Spinraza.

Keeping track of side effects

During your Spinraza 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 a new drug or 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 your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

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

Spinraza can sometimes cause harmful effects in people with certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether this drug is a good treatment option for you.

Talk with your doctor about your health history before starting Spinraza. Be sure to tell them if any of the following factors apply to you:

  • bleeding disorders
  • kidney problems
  • previous allergic reaction to Spinraza
  • pregnancy
  • breastfeeding

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.