Blincyto (blinatumomab) is a prescription drug that’s used to treat acute lymphoblastic leukemia (ALL). Blincyto can cause side effects that range from mild to serious. Examples include infection and infusion-related reactions.

Blincyto is used to treat certain types of acute lymphoblastic leukemia (ALL) in adults and children.

The active ingredient in Blincyto is blinatumomab. (An active ingredient is what makes a drug work.) Blinatumomab is a biologic medication, which means it’s made from parts of living cells.

Blincyto comes as a powder that a healthcare professional (such as a pharmacist) will mix into a liquid solution. You’ll receive Blincyto by intravenous (IV) infusion (an injection into a vein over a period of time).

Keep reading to learn about the common, mild, and serious side effects that Blincyto can cause. For a general overview of the drug, including details about its uses, see this article.

Some people may experience mild to serious side effects during their Blincyto treatment.

Examples of Blincyto’s commonly reported side effects include:

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

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

In most cases, these side effects should be temporary. And some may be easily managed. But if you have any symptoms that are ongoing or bother you, talk with your doctor or pharmacist. Do not stop receiving Blincyto unless your doctor recommends it.

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

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

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

Some serious side effects are common with Blincyto, including neurotoxicity. To learn more, talk with your doctor.

If you develop serious side effects while taking Blincyto, 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 below.
† Blincyto has a boxed warning for this side effect. To learn more, see the “Side effects explained” section below.

Note: After the Food and Drug Administration (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 Blincyto, visit MedWatch.

Blincyto can be used to treat certain types of acute lymphoblastic leukemia (ALL) in children of any age.

Certain side effects of Blincyto may be more common in children than in adults. Examples of mild side effects more commonly reported in children than adults include:

Serious side effects that are more common in children than in adults include:

It’s important to note that Benzyl alcohol is a preservative used in the preparation of Blincyto. It can cause serious side effects in children, including gasping syndrome. With gasping syndrome, children may experience:

Due to this risk, healthcare professionals prepare Blincyto without benzyl alcohol for children who weigh less than 22 kilograms (about 10 pounds).

If you’re concerned about your child’s risk of side effects from Blincyto, talk with their doctor.

Risk of neurotoxicity in children

Blincyto has a boxed warning for the risk of neurotoxicity (damage to the nervous system, which includes the nerve cells and brain).

In Blincyto studies, neurotoxicity occurred at about the same rate in children as in adults. But the symptoms of neurotoxicity were different in infants than in other age groups. Examples of these symptoms include:

  • agitation
  • insomnia (trouble sleeping)
  • sleepiness
  • irritability
  • headache

To learn more about this boxed warning, see the “Side effects explained” section below, or talk with your child’s doctor.

Get answers to some frequently asked questions about Blincyto’s side effects.

Does Blincyto cause hair loss?

No, Blincyto shouldn’t cause hair loss. This wasn’t a side effect reported in Blincyto’s studies.

In some cases, you may use Blincyto after using another treatment for acute lymphoblastic leukemia (ALL). And certain other ALL treatments, such as chemotherapy, may cause hair loss.

If you’re concerned about hair loss during your Blincyto treatment, talk with your doctor.

Can Blincyto cause long-term side effects?

Yes, Blincyto may cause certain long-term side effects. Examples include a low level of red blood cells and of certain white blood cells. It may take weeks or months to get your levels back within a healthy range.

Having a low level of white blood cells can also raise your risk of infection. In some cases, infection may also be a long-term side effect of Blincyto.

If you’re concerned about long-term side effects of Blincyto, talk with your doctor. They can help you manage long-term or bothersome side effects.

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

Risk of neurotoxicity

Blincyto has a boxed warning for the risk of neurotoxicity (damage to the nervous system, which includes the nerve cells and brain). A boxed warning is the most serious warning issued by the Food and Drug Administration (FDA).

In studies, mild neurotoxicity was common in people receiving Blincyto. Neurotoxicity is most likely to occur within the first 2 weeks of starting treatment, but it can occur at any time.

Examples of neurotoxicities that can occur with Blincyto include:

Neurotoxicity with Blincyto may be severe, and in rare cases, it can be life threatening.

If you have an existing neurological condition, such as epilepsy, Blincyto could worsen it. You may also have a higher risk of developing other neurotoxicities.

What might help

During and after your Blincyto infusion, your doctor will monitor you for symptoms of neurotoxicity.

If you have symptoms of neurotoxicity at home between doses, talk with your doctor right away. But if your symptoms seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

If you experience a neurotoxicity, your doctor may need to stop or temporarily pause your Blincyto treatment. Some people may continue receiving Blincyto after a neurotoxicity.

To learn more about the risk of neurotoxicity, talk with your doctor.

Risk of cytokine release syndrome

Blincyto also has a boxed warning for the risk of cytokine release syndrome (CRS). Symptoms of CRS can be similar to those of other side effects of Blincyto, so it’s unclear how common this side effect was in studies of the drug.

CRS is a condition that occurs when your body quickly releases a large amount of cytokines (proteins) into your blood. CRS can be serious or even fatal.

Symptoms of CRS may include:

CRS is most likely to occur within the first 2 days of receiving Blincyto.

What might help

Your doctor will monitor you for CRS whenever you receive doses of Blincyto.

If you have symptoms of CRS, let your doctor know right away. If you have severe symptoms of CRS, your doctor will pause or permanently stop your Blincyto treatment. If your symptoms of CRS are severe, your doctor may also prescribe a steroid treatment, such as dexamethasone, for you.

After your CRS goes away, your doctor may restart your Blincyto treatment again with a lower dose. Then, your doctor may increase your dose of Blincyto after a week if you don’t experience CRS again. But they may also have you permanently stop treatment with Blincyto if you have severe or life threatening CRS symptoms.

Infusion-related reaction

An infusion-related reaction can occur during an intravenous (IV) infusion or in the 48 hours after an infusion. Examples of infusion-related reactions that can occur with Blincyto include:

* Blincyto has a boxed warning for this side effect. To learn more, see the “Risk of cytokine release syndrome” section directly above.

What might help

Your doctor will check for infusion-related reactions during and after your Blincyto infusion.

If you think you’re experiencing an infusion-related reaction, tell your doctor right away.

Depending on how severe your infusion-related reaction is, your doctor may temporarily stop your current infusion until the reaction goes away. Your doctor may restart your Blincyto infusion at a lower dose. Then, they may increase your dose after a week if you don’t have another reaction.

If your infusion-related reaction takes more than 14 days to go away, your doctor may permanently stop your Blincyto treatment.

Infection

Some people may develop infections during their Blincyto treatment. This was a common side effect reported in studies of Blincyto.

Blincyto treats acute lymphoblastic leukemia (ALL) by suppressing your immune system. This increases your risk of infection. An infection can occur from bacteria, viruses, or fungi. In some cases, infections that occur with Blincyto can be serious. However, serious infections were less common than mild infections in Blincyto’s studies.

Your doctor will monitor you for symptoms of infection during your Blincyto treatment. You should also tell your doctor if you have any symptoms of infection, such as:

  • fever
  • chills
  • shortness of breath
  • soreness, swelling, or discoloration (such as redness) of your skin

What might help

During your Blincyto treatment, you can help lower your risk of infection by keeping your skin clean around the catheter where you receive the infusions.

If you have symptoms of an infection, tell your doctor. If they confirm you have an infection, they can prescribe medication to treat it. Examples of treatments include antibiotics or antifungal medications.

Allergic reaction

Like most drugs, Blincyto can cause an allergic reaction in some people. Symptoms can be mild to serious and can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • swelling under your skin, usually in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

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. Examples include:

  • an antihistamine that you swallow, such as Benadryl (diphenhydramine)
  • a product that you apply to your skin, such as hydrocortisone cream

If your doctor confirms you’ve had a mild allergic reaction to Blincyto, they’ll decide whether you should continue receiving it.

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

Keeping track of side effects

During your Blincyto 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 a new drug or using a combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were taking 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

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

Some important things to discuss with your doctor when considering treatment with Blincyto include your overall health and any medical conditions you may have.

Boxed warnings

Blincyto has boxed warnings about the risk of neurotoxicity and the risk of cytokine release syndrome (CRS). Boxed warnings are the most serious warnings from the Food and Drug Administration (FDA).

Risk of neurotoxicity. Blincyto may cause neurotoxicity (damage to the nervous system, which includes the nerve cells and brain). Examples of neurotoxicities include seizure, trouble speaking, and confusion.

Risk of CRS. CRS occurs when your body quickly releases a large amount of a certain protein into your blood. CRS may cause fever, weakness, and nausea. Your doctor will monitor you for CRS when you receive your first dose of Blincyto.

To learn more about these warnings, see the “Side effects explained” section above.

Other warnings

Blincyto 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 Blincyto is a good treatment option for you.

Talk with your doctor about your health history before starting Blincyto. Factors to consider include those described below.

Infection. Blincyto can cause infection, which can be serious in some cases. If you already have an infection, this drug could worsen it.

If you have an infection or symptoms of an infection before or during your Blincyto treatment, tell your doctor. They can determine whether it’s safe to receive or continue receiving Blincyto. Your doctor may need to prescribe medications to treat your infection, such as an antibiotic or antiviral drug.

Allergic reaction. If you’ve had an allergic reaction to Blincyto or any of its ingredients, your doctor will likely not prescribe Blincyto. Ask them what other medications are better options for you.

Past treatment with radiation or leukemia chemotherapy. If you’ve received radiation treatment or chemotherapy drugs for leukemia, tell your doctor before starting Blincyto treatment.

Receiving Blincyto if you’ve had these treatments before may raise your risk of leukoencephalopathy (a kind of nerve damage). Your doctor may order magnetic resonance imaging (MRI) of your brain and spinal cord to check for signs of leukoencephalopathy.

Past infusion-related reaction. Before starting Blincyto, tell your doctor if you’ve ever had an infusion-related reaction to another medication. This could raise your risk of an infusion-related reaction with Blincyto. Examples of infusion reactions include skin rash, high or low blood pressure, fever, or swelling of the face.

Alcohol and Blincyto

There is no known interaction between Blincyto and alcohol. If you drink alcohol, talk with your doctor about how much may be safe to consume during your Blincyto treatment.

Pregnancy during Blincyto treatment

Blincyto is not safe to use during pregnancy. The drug’s use during pregnancy hasn’t been studied, but based on the way it works, it may cause harm to a fetus. This may include low levels of certain white blood cells, which can raise the risk of infection.

If you’re pregnant or planning to become pregnant, talk with your doctor about safer treatment options for you.

If you can become pregnant, your doctor will give you a pregnancy test before you start Blincyto treatment. You’ll also need to use birth control during your Blincyto treatment and for 48 hours after your last dose.

Breastfeeding during Blincyto treatment

It’s not known whether Blincyto is safe to receive while breastfeeding. But because of the risk of harm to a child who’s breastfed, you should not breastfeed during your Blincyto treatment or for 48 hours after your last dose.

If you still have questions about side effects that Blincyto can cause, talk with your doctor. Examples of questions that you may want to ask include:

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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.