Tzield (teplizumab-mzwv) is a brand-name IV infusion that’s prescribed to help delay the worsening of type 1 diabetes in adults and certain children. As with other drugs, Tzield can cause side effects, such as headache and rash.

Tzield can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who received Tzield in clinical trials:

* For more information about this side effect, see “Side effect specifics” below.

Mild side effects can occur with Tzield use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Tzield’s prescribing information.

Mild side effects that have been reported with Tzield include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you develop a side effect during Tzield treatment and want to tell the FDA about it, visit MedWatch.

* For more information about this side effect, see “Side effect specifics” below.
† An allergic reaction is possible after receiving Tzield. To learn more, see the “Side effect specifics” section below.

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

If you develop serious side effects during treatment with Tzield, 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 and their symptoms include:

* For more information about this side effect, see “Side effect specifics” below.
† An allergic reaction is possible after receiving Tzield. To learn more, see the “Side effect specifics” section below.

Learn more about some of the side effects that Tzield may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Tzield.

Low white blood cell count

Tzield may cause a low white blood cell count. Specifically, it can cause lymphopenia (low lymphocyte count) and neutropenia (low neutrophil count). In clinical trials, lymphopenia was a commonly reported side effect.

Having a low level of white blood cells typically doesn’t cause symptoms. However, it can increase your risk of developing an infection. Symptoms of an infection may include:

  • fever
  • runny nose
  • cough
  • fatigue

What you can do

The decrease in white blood cells was usually temporary and resolved on its own. Your doctor will likely run blood tests to monitor your white blood cell count during treatment with Tzield. If you have a persistent, severely low white blood cell count, your doctor may recommend stopping the drug.

If you notice any symptoms of infection, let your doctor know right away. If your infection is serious, your doctor may stop treatment with Tzield. After treating your infection, they’ll determine whether it’s safe for you to receive Tzield again. In some cases, they may recommend a different drug for your diabetes.

Cytokine release syndrome

It’s possible for Tzield to cause a condition called cytokine release syndrome (CRS). This was a common side effect reported in the drug’s clinical trials.

CRS happens when an overactive immune system causes harmful levels of inflammation in your body. Symptoms vary depending on the severity of inflammation but can include:

What you can do

To help prevent CRS, your doctor will typically give you certain medications before each dose of Tzield. These may include:

Your doctor will also order a liver function test to monitor your liver enzymes during treatment. If your liver enzyme levels become too high, you may need to stop treatment with Tzield.

Tell your doctor right away if you have any symptoms of CRS. You may need to stop therapy with Tzield if you develop serious CRS.

Your doctor will determine whether it is safe for you to continue receiving Tzield.

Allergic reaction

As with most drugs, Tzield can cause an allergic reaction in some people. In clinical trials, severe allergic reactions were rare.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should continue receiving Tzield. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Be sure to talk with your doctor about your health history before you start treatment with Tzield. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health. These include:

Recent vaccination: Tell your doctor if you’ve recently received a vaccine or are scheduled to receive one. Tzield can affect how well a vaccine works and can cause your vaccine to be less effective. Your doctor will likely want to make sure you’re up to date on your vaccinations before starting therapy with Tzield.

Infection: If you have an active or recurring infection, such as Epstein-Barr virus (EBV), talk with your doctor. Tzield can weaken your immune system, leading to a higher risk of infection. Due to the way this drug works, it may increase the risk that a recurring infection will come back. If you have an infection, your doctor will want to treat it before you start receiving Tzield. However, in some cases, they may recommend a different treatment option for you.

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

Pregnancy or breastfeeding: Tzield may not be safe to receive if you’re pregnant or breastfeeding your child. Talk with your doctor before treatment with Tzield if you’re pregnant, planning to become pregnant, or breastfeeding.

If you become pregnant during treatment with this drug, tell your doctor right away. They will likely recommend that you stop treatment with Tzield immediately. They may also recommend joining the drug’s pregnancy registry. This registry helps the drug’s manufacturer track outcomes and side effects from exposure to Tzield during pregnancy. You can sign up for this registry by calling 800-633-1610.

Alcohol consumption: There are no known interactions between Tzield and alcohol. Talk with your doctor if you have questions about how much alcohol is safe to drink during treatment with Tzield.

Like most medications, Tzield can cause mild and serious side effects. In some cases, Tzield can cause serious side effects that may require treatment. Talk with your doctor if you experience side effects that are bothersome or become severe.

If you’d like to learn more about Tzield, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

  • More information about Tzield: For details about other aspects of Tzield, refer to this article.
  • Cost: If you’d like to learn about Tzield and cost, see this article.
  • Dosage: For information about the dosage of Tzield, view this article.
  • A look at your condition: For details about type 1 diabetes, see our diabetes hub.

Disclaimer: Medical News Today 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.