Inflectra (infliximab-dyyb) is a brand-name IV infusion that’s prescribed for certain autoimmune diseases. As with other drugs, Inflectra can cause side effects, such as fatigue and headache.

Inflectra is approved by the Food and Drug Administration (FDA) to treat:

Inflectra contains the active ingredient called infliximab-dyyb, which is a biologic.†

Read on to learn about potential common, mild, and serious side effects. For a general overview of Inflectra, including details about its uses, see this article.

* For this use, Inflectra is prescribed with another drug called methotrexate (Trexall).
† The reason “-dyyb” appears at the end of the drug’s name is to show that the drug is distinct from similar medications that may be created in the future.

Inflectra 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 took Inflectra in clinical trials:

  • mild infection, such as sinus infection or cold
  • headache
  • abdominal pain
  • reaction during or after your infusion*
  • fatigue*

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

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

Mild side effects that have been reported with Inflectra 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 side effects of the medication. If you develop a side effect while receiving Inflectra and want to tell the FDA about it, visit MedWatch.

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

Inflectra may cause serious side effects. Although serious side effects aren’t common, they can occur. So you should be aware of possible serious side effects and symptoms. The list below may not include all possible serious side effects of the drug. For more details, you can refer to Inflectra’s prescribing information.

If you develop serious side effects while receiving Inflectra, 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:

  • Heart failure. Symptoms can include:
    • shortness of breath
    • swelling of the legs or feet
    • weight gain
    • cough
  • Liver problems. Symptoms can include:
    • jaundice
    • abdominal pain
    • nausea or vomiting
  • Nervous system conditions. Symptoms can include:
    • weakness
    • tingling or numbness
    • vision loss
    • seizures
  • Lupus-like syndrome. (With this condition, you’ll have symptoms that mimic Lupus disease) Symptoms can include:
    • shortness of breath
    • joint pain
    • rash on your cheeks or arms
  • Decreased blood cell levels, specifically, leukopenia or neutropenia (low white blood cell levels) or thrombocytopenia (low platelet level). Symptoms can include:
    • bruising or bleeding more easily
    • fever
    • pale-looking skin
  • Hepatitis B reactivation. This can only occur if you’ve had the hepatitis B virus in the past. Symptoms can include:
    • nausea or vomiting
    • abdominal pain
    • jaundice
  • Certain cancers.*†
  • Severe infection.*†
  • Reaction during or after your infusion.†
  • Severe allergic reaction.†

* Inflectra has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA).
† To learn more about this side effect, see the “Side effect specifics” section below.

Inflectra is approved to treat Crohn’s disease (CD) or ulcerative colitis (UC) in children ages 6 years and older. In most cases, adults and children experience similar side effects during Inflectra treatment.

However, some side effects that occurred in adults, occurred more commonly in children. For example, children receiving Inflectra for CD had an increased risk of:

Children receiving Inflectra for UC also experienced infection more often than adults.

If your child is having Inflectra treatment and you’re concerned about the possible side effects the drug may cause, talk with your child’s doctor.

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

Inflectra may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

Is hair loss a side effect of Inflectra?

No, hair loss is not a known side effect of Inflectra. Hair loss did not occur in clinical trials of the drug. So you should not experience hair loss from Inflectra treatment.

However, it’s possible for certain autoimmune conditions to cause hair loss. For example, hair loss can be a symptom of rheumatoid arthritis. And Inflectra is used to treat this condition. (To learn more, see this article.)

In addition, other medications that are used for autoimmune conditions may cause hair loss. For example, if you have rheumatoid arthritis, your doctor will prescribe Inflectra with methotrexate (Trexall). This drug can cause hair loss as a side effect.

If you notice hair loss during your treatment with Inflectra, tell your doctor. They can help determine what may be causing your hair loss. Also, your doctor may recommend ways to decrease your hair loss. This may include using an over-the-counter medication such as minoxidil (Rogaine).

Should I expect to gain weight with Inflectra?

No, you should not expect to gain weight with Inflectra treatment. Weight gain was not a side effect that people receiving Inflectra reported in clinical trials.

However, it’s possible to develop weight gain as a symptom of other side effects that Inflectra may cause. For example, Inflectra can cause new or worsening heart failure. And one symptom of heart failure is sudden weight gain. (To learn more about heart failure, see the “Serious side effects of Inflectra” section above.)

If you notice unexpected or sudden weight gain during your treatment with Inflectra, tell your doctor. They can help you determine what may be causing your weight gain. And they’ll recommend the best ways to manage it.

Do Inflectra and Remicade have the same side effects?

Inflectra and Remicade have similar side effects. This is because Inflectra is a biosimilar form of Remicade, a biologic.

Common side effects of both drugs include:

  • mild infection, such as a sinus infection or cold
  • headache
  • abdominal pain
  • fatigue
  • reaction during or after your infusion*

Because Remicade is a biologic drug, it’s made from living organisms. So it’s not possible to copy Remicade exactly. However, Inflectra has been shown to be just as safe and effective as Remicade.

Your doctor may recommend switching from Remicade to Inflectra based on cost or your insurance coverage. In most cases, biosimilars cost less than the parent drug they are based on.

If your doctor recommends switching from Remicade to Inflectra, you may still experience the same side effects.

If you have questions about the side effects of Remicade and Inflectra, talk with your doctor or pharmacist. Also, talk with them if you are interested in switching from Remicade to Inflectra.

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

Are Inflectra’s side effects different when the drug is used for Crohn’s disease?

No, side effects of Inflectra shouldn’t be different when the drug is used to treat Crohn’s disease (CD). Side effects can occur in adults receiving the drug for CD or any other condition. These side effects can include abdominal pain, infection, or reaction during or after your infusion.*

However, side effects in children receiving Inflectra for CD may be slightly different than in adults. For example, children can experience flushing or bone fracture (broken bone) along with the typical side effects seen in adults.†

If you have questions about side effects that may occur during your CD treatment, talk with your doctor.

* For more information about this side effect, see “Side effect specifics” below.
† For more information about Inflectra’s side effects in children, see the “Side effects in children” section above.

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

Certain cancers

It’s possible to develop cancer during treatment with tumor necrosis factor (TNF) blocker drugs, including Inflectra. In some cases, this can be life threatening. In fact, Inflectra has a boxed warning for the risk of certain cancers. A boxed warning is the most serious warning recommended by the Food and Drug Administration (FDA). It alerts doctors and patients about the risks of taking a drug.

Cancer was not a common side effect in clinical trials of Inflectra. However, it can still occur in children or adults.

The cancers that have occurred in people receiving TNF blockers include lymphoma, skin cancer, cervical cancer, and hepatosplenic T-cell lymphoma (HSTCL). (HSTCL is a rare form of cancer that affects your liver and spleen.)

Possible symptoms of these cancers can include:

  • night sweats or fevers
  • fatigue
  • a mole that’s changing shape or color
  • an open sore or skin lesion that does not go away

It’s important to note most people who developed HSTCL received other drugs that affect the immune system, such as azathioprine or 6-mercaptopurine. They had treatment with these drugs before or with Inflectra treatment. Most people who developed HSTCL in clinical trials were receiving the drug for Crohn’s disease or ulcerative colitis.

What you can do

If you develop any symptoms of cancer, it’s important to contact your doctor right away. They can help determine what may be causing your symptoms and the best ways to treat them.

Your doctor will also monitor you for any changes throughout your treatment with Inflectra. They may recommend regular skin cancer screenings to help catch this cancer quickly if it develops.

In addition, be sure to tell your doctor if you’ve ever had cancer or if you’re taking any other medications. These may further increase your risk of cancer. In some cases, your doctor may recommend a different treatment option for you.

Severe infection

Inflectra has a boxed warning for the risk of severe infection. A boxed warning is the most serious warning from the FDA. The purpose of a boxed warning is to alert doctors and patients about the risks of taking a certain medication. Severe infection was rare in clinical trials. However, it can still occur.

Inflectra is an immunosuppressant (a drug that weakens your immune system). So it can increase your risk of severe infection during treatment. This can include viral, fungal, or bacterial infections, which can be life threatening.

Examples of severe infections people have experienced with Inflectra include pneumonia (inflammation of the lungs) and sepsis. (With sepsis, you have a severe response to an infection, which may lead to serious problems, including death.) It’s also possible for past infections of hepatitis B or tuberculosis (TB) to worsen or reactivate (come back) during Inflectra treatment. In some cases, TB reactivation was fatal.

Symptoms of severe infection may include:

  • fever
  • sore throat
  • cough
  • trouble breathing

What you can do

If you develop any of the symptoms above, tell your doctor. They can determine whether you have any current infections and recommend ways to treat them. In some cases, they may recommend an antibiotic or another medication to help your body fight an infection.

Before you start treatment with Inflectra, your doctor can help determine whether Inflectra is a safe treatment option for you. So be sure to tell them if you currently have an infection, have infections often, or they keep coming back. These can increase your risk of developing an infection with Inflectra treatment.

Also, your doctor will order a blood test to be sure that you don’t have hepatitis B or TB. If you have either of these infections, your doctor will likely recommend treatment with medication before you start receiving Inflectra.

If you have questions about this side effect, talk with your doctor. They can discuss the risks of developing a severe infection.

Fatigue

Some people may experience fatigue after receiving Inflectra treatment. This was not one of the most common side effects in clinical trials. However, it can still occur during your treatment.

What you can do

If you notice fatigue during your treatment with Inflectra, tell your doctor. In some cases, fatigue may be related to other side effects of Inflectra, such as infection or liver problems. Your doctor may recommend some testing to find out what’s causing your fatigue.

If you are experiencing fatigue related to Inflectra, your doctor may recommend ways to decrease the severity of this side effect.

Reaction during or after infusion

Inflectra is given by intravenous (IV) infusion at a doctor’s office, hospital, or infusion center. So it’s possible to develop a reaction during or after Inflectra infusions. This reaction is also known as an infusion-related reaction.

Most infusion-related reactions occur during the infusion or within 1 hour after your infusion is complete. This side effect was commonly reported in clinical trials. And it was one of the most common reasons that people stopped receiving the drug.

Symptoms can include trouble breathing, flushing, headache, or skin rash.

Infusion reactions can be serious. And they can lead to stroke or heart problems, including heart attack. In clinical trials of Inflectra, serious infusion reactions occurred up to 48 hours after the infusion.

Symptoms of a stroke or heart problems can include:

  • chest pain
  • pain in the jaw, neck, back, or arm
  • shortness of breath
  • weakness on one side of the body

What you can do

It’s important to be aware of the symptoms of an infusion-related reaction. If you notice any symptoms during your Inflectra infusion, tell your doctor right away. They may recommend stopping the infusion.

If you develop symptoms of an infusion-related reaction after your infusion is complete, call your doctor or go to the hospital to get treatment for your reaction.

In some cases, your doctor may recommend taking medications such as diphenhydramine (Benadryl) or acetaminophen (Tylenol) before your Inflectra infusion. These medications can help prevent an infusion reaction.

Allergic reaction

As with most drugs, Inflectra can cause an allergic reaction in some people. This side effect was rare in clinical trials of Inflectra.

Symptoms can be mild or serious, and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your lips, eyelids, feet, or hands
  • 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 keep receiving Inflectra. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Before you start treatment with Inflectra, be sure to tell your doctor about any other medical conditions that you have. Your doctor can help you determine whether Inflectra is a safe treatment option for you.

Boxed warnings

This drug has boxed warnings about the risks of certain cancers and severe infection. These are serious warnings from the Food and Drug Administration (FDA). For details, see the “Side effect specifics” section above.

Other precautions

Be sure to talk with your doctor about your health history before you receive Inflectra. This drug may not be the right treatment option for you if you have certain medical conditions or other factors that affect your health. These are called drug-condition or drug-factor interactions. The conditions and factors to consider include:

Infection: Before starting treatment with Inflectra, tell your doctor if you have any infections. You should also tell them if you get infections often or if they keep coming back. Inflectra treatment may increase your risk of infection or worsen a current infection. So if you have an increased risk of infection, receiving this drug can increase it further. Talk with your doctor to see whether it’s safe for you to receive Inflectra.

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

Diabetes: Before you start receiving Inflectra, tell your doctor if you have diabetes. This medication may weaken your immune system. If you have diabetes and you’re receiving Inflectra, you may have an increased risk of infection. Due to this risk, your doctor may recommend more frequent monitoring to be sure that you do not develop an infection.

Immune system conditions: If you have any conditions that affect your immune system, tell your doctor before you start treatment with Inflectra. This medication can weaken your immune system, so if you already have a condition that affects your immune system, receiving Inflectra may worsen your condition. The drug can also increase your risk of infection. Due to this risk, your doctor may recommend monitoring you more often for infection symptoms. In some cases, they may recommend a different treatment option for you.

Tuberculosis (TB): Tell your doctor if you’ve ever had TB. Inflectra can weaken your immune system, which can cause your TB infection to come back or worsen. Due to this risk, your doctor will test you for TB before you start treatment with Inflectra. If you have TB, they may recommend treating it with medication before you start receiving Inflectra. In some cases, they may recommend a different treatment option for you.

Hepatitis B: If you’ve ever had hepatitis B, tell your doctor before starting treatment with Inflectra. Inflectra may weaken your immune system, which can increase your risk of hepatitis B virus reactivation. Your doctor will test you for hepatitis B before you start Inflectra treatment. They may also recommend monitoring you for symptoms of hepatitis B during your Inflectra treatment. In some cases, they may recommend stopping Inflectra treatment and trying another drug for your condition.

Cancer: Inflectra can increase your risk of developing cancer. If you’ve ever had cancer, tell your doctor before starting Inflectra treatment. This is important to do because the drug may increase the risk of your cancer coming back. Talk with your doctor to see whether it’s safe for you to receive this medication.

Heart failure: Tell your doctor if you have a history of heart failure. Inflectra may increase your risk of heart failure. It can also worsen existing heart failure, so your doctor may recommend more frequent monitoring of heart failure symptoms. This is to be sure that your condition does not worsen. They may also recommend a lower Inflectra dose or a different treatment option for you.

Liver problems: If you have any liver problems, be sure to tell your doctor before starting treatment with Inflectra. This medication may cause liver problems, so if you already have liver problems, Inflectra can make your condition even worse. Due to this risk, your doctor may monitor you more often throughout your treatment. This is to be sure that your liver problems aren’t worsening.

Blood problems: If you have any blood problems, such as low levels of white blood cells, red blood cells, or platelets, tell your doctor before you start treatment with Inflectra. This medication may decrease your blood cell levels, so if you already have low blood cell levels, receiving Inflectra can further decrease them. This can make your condition worse and may increase your risk of infection or bleeding.

Your doctor may check your blood cell levels before starting Inflectra treatment. In some cases, they may monitor you more often while you’re receiving Inflectra. Other times, they may recommend a different treatment option for you.

Nervous system problems: It’s possible for Inflectra to cause nervous system problems such as seizures or optic neuritis. If you already have a nervous system problem, receiving Inflectra may worsen your condition. Your doctor can help determine whether it may be safe for you to receive Inflectra with your specific condition.

Alcohol with Inflectra

There aren’t any known interactions between alcohol and Inflectra.

However, it’s possible for alcohol to worsen side effects of Inflectra. For example, Inflectra may cause headache or fatigue. Alcohol may also cause these side effects. So drinking alcohol during Inflectra treatment may increase your risk of these side effects.

Also, both drinking alcohol and receiving Inflectra may cause liver problems. So your risk of liver problems may increase if you drink alcohol during your treatment.

Alcohol may also worsen symptoms of your condition. For example, alcohol can worsen ulcerative colitis or Crohn’s disease symptoms. And Inflectra is used to treat these conditions.

If you’d like to drink alcohol while you’re receiving Inflectra, talk with your doctor. They can help determine whether it’s safe for you.

Pregnancy and breastfeeding while receiving Inflectra

Below is some information about pregnancy and breastfeeding during Inflectra treatment.

Pregnancy

At this time, it’s not known for sure whether it’s safe to receive Inflectra during pregnancy.

Studies did not show an increased risk of congenital anomalies (also known as birth defects) when pregnant people received infliximab. (Infliximab is a biosimilar version of Inflectra.) However, more research is needed to determine whether Inflectra is safe to receive during pregnancy.

It’s important to note that if a pregnant person receives Inflectra, the developing fetus may be exposed to the drug. And Inflectra can reduce the fetus’s immune system function. This can increase their risk of infection after birth.

Also, live vaccines should not be given to a child who was exposed to Inflectra until 6 months after birth. This is because live vaccines contain weakened live viruses. And if a child has reduced immune system function, getting these vaccines may make them sick.

However, if you’re pregnant and have Crohn’s disease, ulcerative colitis, or rheumatoid arthritis, it’s important to get treatment. This is because these conditions can increase certain risks during pregnancy. Your doctor can help you determine the best way to treat your condition during pregnancy.

If you’re pregnant or planning to become pregnant, talk with your doctor before receiving Inflectra.

Breastfeeding

Currently, it’s unknown whether it’s safe to receive Inflectra while breastfeeding.

Infliximab is known to pass into breast milk. So a child who is breastfed will likely be exposed to Inflectra. However, this is not known to increase the risk of infection or developmental problems in a child. This is because the child’s digestive system may break down the drug. So Inflectra may not cause them to experience any side effects.

If you’re breastfeeding or planning to breastfeed, talk with your doctor before receiving Inflectra treatment.

Inflectra may cause side effects during treatment, most of which are mild. However, sometimes, this medication may cause serious side effects.

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

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

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.