If you have certain types of arthritis or psoriasis, your doctor may recommend that you take Enbrel (etanercept).

Enbrel is a prescription medication that’s used to treat:

To learn more about these uses, see this in-depth article.

Enbrel is injected once weekly. It’s usually meant for long-term use.

Knowing the possible side effects of Enbrel can help you decide if this drug may be right for you. Keep reading to learn about the possible side effects of Enbrel.

Like most drugs, Enbrel may cause side effects in some people. Your doctor will suggest Enbrel if they think the benefits you’ll receive from the drug outweigh your risk for side effects.

The more commonly reported side effects of Enbrel may include:

The next two sections include more of the mild and serious side effects that could happen with Enbrel.

Enbrel may cause mild side effects in some people. Examples of side effects that have been reported include:

  • respiratory infections, such as sinus infections or the flu
  • injection site reactions, such as irritation or pain
  • rash
  • itchy skin
  • fever
  • diarrhea

This list may not include all of the possible mild side effects of Enbrel. For more information, see Enbrel’s medication guide.

In most cases, mild side effects should be temporary. And some may be easily managed, too. But if you have any symptoms that are ongoing or that bother you, talk with your doctor or pharmacist. Don’t stop using Enbrel unless your doctor recommends it.

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 Enbrel, visit MedWatch.

In rare cases, Enbrel can cause serious side effects in some people. You may have an increased risk for serious side effects if you take other drugs with Enbrel that can weaken your immune system.

Serious side effects that have been reported with Enbrel include:

If you have questions about your specific risk for serious side effects, talk with your doctor.

* For more information on this side effect, see “Side effects explained” below.
† Enbrel has a boxed warning for this side effect. This is the most serious warning from the Food and Drug Administration (FDA). To learn more, see the “Side effects explained” section below.

Enbrel can be used in children with the following conditions:

In general, side effects seen in children are similar to those seen in adults. However, Enbrel has a boxed warning for the risk of cancer in children and young adults. (See the “Side effects explained” section to learn more.) In some cases, cancer from Enbrel has led to death.

Before your child uses Enbrel, talk about the risks and benefits with their doctor.

Get answers to some common questions about Enbrel’s side effects.

How do I stop the side effects from Enbrel?

Side effects from Enbrel are usually mild and may be temporary. But if they bother you, you can take steps to manage certain side effects. To learn more, see the “Side effects explained” section below.

Will I have side effects at the site of my Enbrel injection?

It’s likely. Injection-site reactions is one of the most commonly reported side effects of Enbrel. These may include:

  • redness or discoloration
  • itching
  • pain
  • swelling
  • bleeding
  • bruising

Injection site reactions are more common in the first month of treatment. In most cases, these reactions go away about 3 to 5 days after receiving your dose.

If you’re concerned about injection-site reactions during your Enbrel treatment, talk with your doctor.

Does Enbrel cause weight loss or weight gain?

No, Enbrel shouldn’t cause weight gain or weight loss. These side effects weren’t reported in studies of Enbrel.

However, unexplained weight changes can sometimes be a symptom of more serious side effects. Or it could be a sign of a different health condition.

Let your doctor know right away if you have unexplained weight loss or weight gain after starting Enbrel. They may want to do a physical exam or order blood tests. This can help your doctor find out why you’ve lost or gained weight.

Is hair loss a side effect of Enbrel?

No. Hair loss wasn’t a side effect of Enbrel during studies. However, some people with rheumatoid arthritis or psoriatic arthritis use methotrexate along with Enbrel. And methotrexate could cause hair loss.

Also, hair loss can sometimes be caused by plaque psoriasis, which Enbrel is used to treat. With plaque psoriasis, itchy raised skin patches can form on the scalp. Scratching at these plaques could contribute to hair loss.

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

Can Enbrel cause side effects for my heart?

It’s possible. Although heart side effects weren’t seen in studies, there have been reports of Enbrel causing heart problems in some people. However, it’s unclear how often this has happened.

For example, it’s been reported that some people with congestive heart failure had worse symptoms during their Enbrel treatment. There have also been rare reports of people being newly diagnosed with heart failure after using Enbrel.

While using Enbrel, call your doctor right away if you notice any symptoms of congestive heart failure:

  • shortness of breath
  • fatigue (lack of energy)
  • cough
  • swelling in legs and ankles

During your Enbrel treatment, your doctor will monitor your heart closely. Let your doctor know if you’ve had any heart problems, and they’ll discuss the risks and benefits of Enbrel with you.

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

Serious infections

Enbrel has a boxed warning for serious infections. This is the most serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous.

People using Enbrel have an increased risk for serious infections. This is because Enbrel may weaken your immune system. Serious infections that are possible with Enbrel include tuberculosis (TB), fungal, bacterial, or viral infections. These infections could lead to a hospital stay or death.

Let your doctor know if you’ve ever had tuberculosis (TB) or were exposed to someone with TB. Enbrel can cause TB to reactivate (flare up). Your doctor will test you for TB before you start Enbrel. If you do have TB, your doctor likely won’t have you start using Enbrel until your TB is treated.

What might help

Before starting Enbrel, tell your doctor if you have any current infections or have had infections in the past that have come back. Before you begin treatment with Enbrel, your doctor will test you for TB. If your test confirms you have TB, it may need to be treated before you start taking Enbrel.

While using Enbrel, call your doctor right away if you have any symptoms of a serious infection, such as:

  • fever
  • nausea or vomiting
  • diarrhea
  • shortness of breath

During your treatment, your doctor will monitor you for symptoms of a serious infection. If you do get a serious infection, your doctor will likely stop your Enbrel treatment.

If you’re concerned about your risk for a serious infection from Enbrel, talk with your doctor.

Risk of cancer

Enbrel also has a boxed warning for the risk of cancer. Enbrel has been linked with certain types of cancer (such as lymphoma and skin cancer) in children and young adults.

What might help

Before you begin treatment with Enbrel, tell your doctor if you have any family history of cancer. If you have a higher risk for cancer, you may need to be monitored more closely during your Enbrel treatment. This may include additional blood tests and routine skin examinations.

While using Enbrel, call your doctor right away if you have any symptoms of cancer, such as:

  • ongoing fever without infection
  • night sweats, fever, or chills
  • weight loss and reduced appetite
  • ongoing fatigue (lack of energy)
  • skin changes, such as a new wart

Before your child uses Enbrel, talk with their doctor about the risks and benefits of the drug.

Neurologic side effects

In rare cases, Enbrel can cause neurologic (nervous system) conditions or make an existing condition worse. Symptoms of neurologic problems may include:

  • confusion
  • memory loss
  • feeling disoriented
  • vision changes or vision loss
  • muscle weakness

What might help

If you have any of the above side effects while using Enbrel, talk with your doctor right away. These symptoms could be a sign of a neurological condition such as multiple sclerosis (MS), seizures, or optic neuritis (swelling of the eye nerves). Your doctor may order blood tests or refer you to see a neurologist for possible treatment.

Injection site reactions

A common side effect of Enbrel is a reaction at the site where the drug is injected. These side effects are usually mild and may include:

  • redness or discoloration
  • itching
  • pain
  • swelling
  • bleeding
  • bruising

What might help

Injection site reactions are more common in the first month of treatment. In most cases, these reactions go away about 3 to 5 days after receiving your dose. But if you have injection-site reactions that bother you, you could try using a cool compress to soothe the area. Or ask your doctor for other suggestions on how to ease injection-site reactions.

Blood disorders

In rare cases, some people using Enbrel may experience low levels of certain types of blood cells. An example of a blood disorder that can occur is pancytopenia, and its symptoms can include:

  • ongoing fever
  • bruising
  • bleeding more easily than usual
  • pale-looking skin or gums

What might help

During your treatment with Enbrel, your doctor will monitor you for blood disorders by checking your blood cell levels.

If you notice any symptoms of your blood being abnormal, such as excessive bleeding from gums while flossing, let your doctor know. If any of your blood cell levels are low, your doctor might have you stop Enbrel while you’re monitored or treated for low blood cells.

Allergic reaction

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

  • rash
  • itchiness
  • flushing (warmth, swelling, redness, or discoloration in your skin)
  • 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 might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest an over-the-counter oral antihistamine, such as diphenhydramine (Benadryl), or topical product, like hydrocortisone cream, to manage your symptoms.

If your doctor confirms you had a mild allergic reaction to Enbrel, they’ll decide if you should continue using 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 had a serious allergic reaction to Enbrel, they’ll discuss your treatment options with you.

Keeping track of side effects

During your Enbrel treatment, consider keeping notes on any side effects you’re having. Then, you can share this information with your doctor. This is especially helpful to do when you first start taking new drugs or using a combination of treatments.

Your side effect notes can include things like:

  • what dose of drug you were taking when you had the side effect
  • how soon after starting that dose you had the side effect
  • what your symptoms were from the side effect
  • how it affected your daily activities
  • what other medications you were also taking
  • any other information you feel is important

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

Enbrel has several warnings that may affect whether or not you can safely use this drug.

Boxed warnings

Enbrel has boxed warnings about serious infections and the risk of cancer. Boxed warnings are the most serious warnings from the Food and Drug Administration (FDA).

Serious infections. People using Enbrel have an increased risk for serious infections that may lead to a hospital stay or death. See your doctor right away if you have any symptoms of a serious infection, such as fever, nausea, vomiting, diarrhea, or shortness of breath. Let your doctor know if you’ve ever had tuberculosis (TB) or were exposed to someone with TB. Enbrel can cause TB to reactivate (flare up).

Risk of cancer. Enbrel has been associated with certain types of cancer (such as lymphoma) in children and young adults.

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

Other warnings

Enbrel may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your doctor about your health history before you take Enbrel. Factors to consider include those in the list below.

Diabetes. If you have diabetes, using Enbrel may raise your risk for hypoglycemia (low blood sugar). Your doctor may lower your dose of diabetes medications while using Enbrel. This can help prevent your blood sugar levels from getting too low. Also, having diabetes raises your risk for infection, and infections can occur during treatment with Enbrel.

Other infections. If you have a current infection, Enbrel can make it worse. This includes any type of fungal, bacterial, or viral infections, even minor colds or skin wounds. Before starting your Enbrel treatment, tell your doctor if you have an infection or have had one recently.

Sepsis. You shouldn’t use Enbrel if you have sepsis. Sepsis is a very serious infection that affects your entire body. Because Enbrel can weaken your immune system, it could make sepsis even worse.

Neurologic reactions. Using Enbrel could make some neurological (nervous system) conditions worse. If you have multiple sclerosis (MS), seizures, optic neuritis, or any other brain or nervous system condition, talk with your doctor before using Enbrel. They may want to discuss the risks and benefits of Enbrel with you.

Hepatitis B reactivation. If you’ve had hepatitis B, using Enbrel could make the hepatitis B virus reactivate (flare up). If not treated, hepatitis B can cause serious liver problems. Your doctor will check you for hepatitis B with a blood test before prescribing Enbrel.

Vaccines. Because Enbrel can weaken the immune system, you shouldn’t get live vaccines during your Enbrel treatment. Live vaccines contain a weakened form of a virus or bacterium. Examples of live vaccines include:

It’s best to get caught up with any vaccines you need before starting Enbrel. If you have questions about what vaccines you may need, ask your doctor or pharmacist.

Immune reactions such as lupus-like syndrome. It’s possible that Enbrel could cause your immune system to attack your own healthy tissues. In rare cases, lupus-like syndrome and autoimmune hepatitis have occurred. Your doctor will monitor you closely for immune reactions during your treatment. If you do experience any of these reactions, you doctor may stop your Enbrel treatment.

Certain other drugs. Enbrel shouldn’t be used with certain other medications. These include anakinra, abatacept, cyclophosphamide, and sulfasalazine. If you’re taking any of these medications, let your doctor know before starting Enbrel. They may make a change to your treatment plan.

Alcoholic hepatitis. Alcoholic hepatitis is inflammation (swelling and damage) of the liver caused by heavy alcohol use. It’s possible that people who have moderate-to-severe alcoholic hepatitis may have a higher risk for death when taking Enbrel. If you have alcoholic hepatitis, talk with your doctor about the best treatment option for your condition.

Allergic reaction. If you’ve had an allergic reaction to Enbrel or any of its ingredients, you shouldn’t take Enbrel. Ask your doctor what other medications are better options for you.

Alcohol use and Enbrel

It should be safe for you to drink alcohol during your Enbrel treatment. However, certain drugs that are often prescribed along with Enbrel should not be used with alcohol. This may include methotrexate or certain pain medications such as oxycodone, depending on your condition.

If you drink alcohol, talk with your doctor about how much may be safe for you to drink with your condition and treatment plan.

Pregnancy and breastfeeding while taking Enbrel

Before starting Enbrel, tell your doctor if you’re pregnant or planning to become pregnant. Enbrel should only be used during pregnancy in certain cases and after discussing the risks with your doctor.

If you’re breastfeeding or planning to breastfeed, talk with your doctor before using Enbrel. This drug may pass into breast milk in very small amounts. However, there aren’t any reports of how this may affect a breastfed child. Talk with your doctor to learn more.

Enbrel is used to treat certain types of arthritis and psoriasis. When you’re considering Enbrel as a treatment option, it’s helpful to know about its possible side effects. For most people, side effects of this drug are mild. But serious side effects are possible.

Talk with your doctor or pharmacist if you have questions about Enbrel or its side effects. Here are some example questions to get you started.

  • Do I have a higher risk for side effects of Enbrel than other people?
  • Would Enbrel interact with any other medications I’m taking?
  • What can I do to lower my risk for serious infections with Enbrel?
  • Is it safe for me to get vaccines while taking Enbrel?

You can sign up to receive our psoriasis or rheumatoid arthritis newsletters if you use Enbrel to treat either of these conditions.

Q:

I read that fever is a possible side effect of Enbrel. If I develop a fever while taking Enbrel, how would I know whether I’m having a side effect of the drug or if it’s a symptom of an infection?

Anonymous patient

A:

Fever can be a mild side effect of Enbrel. But in some cases, it may be a symptom of a more serious side effect caused by Enbrel, such as infection or blood disorders.

Enbrel can lower your body’s ability to fight infection. Symptoms of infection include fever, sweats or chills, cough or flu-like symptoms, or shortness of breath. Enbrel can also cause certain blood disorders such as pancytopenia. Symptoms of pancytopenia include ongoing fever, bruising or bleeding very easily, or pale-looking skin or gums.

If you’re using Enbrel and develop a fever, call your doctor right away. And tell them if you’ve experienced any of the other side effects of infection or blood disorders mentioned above. Your doctor can help determine what may be causing your fever and what your next steps should be.

Neal Patel, PharmDAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

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.