Erelzi (Etanercept-Szzs) - Subcutaneous


Erelzi (etanercept-szzs) carries a boxed warning for serious infections and malignancies, including an increased risk of serious infections leading to hospitalization or death, including tuberculosis (TB), bacterial sepsis, invasive fungal infections (such as histoplasmosis), and infections due to other opportunistic pathogens. Lymphoma and other malignancies, some fatal, have been reported in children and adolescents treated with TNF blockers, including etanercept products.

Stop taking Erelzi if you develop a severe infection or sepsis during treatment. Before starting Erelzi, your healthcare provider should perform a test for latent TB; if positive, you should be treated for TB before starting Erelzi. Your healthcare provider may monitor you for active TB during treatment, even if the initial latent TB test is negative.

What Is Erelzi?

Erelzi (etanercept-szzs) is an injectable medication used to treat several types of autoimmune diseases. Autoimmune diseases occur when the body’s immune system, meant to protect you from foreign bodies like viruses and bacteria, attacks your cells instead and causes conditions like rheumatoid arthritis and psoriasis.

This drug is called a tumor necrosis factor inhibitor, or TNF inhibitor. TNF is a protein that assists with metabolism and blood clotting, but too much of it can cause inflammation and joint damage, like in rheumatoid arthritis and other autoimmune conditions. Erelzi blocks the activity of this protein, decreasing inflammation.

The generic name for Erelzi is etanercept-szzs. Erelzi is a biosimilar product for the biologic drug Enbrel (etanercept). Like other biologic drugs, Enbrel is made from living cells through a complex process, making it an expensive product. Erelzi is highly similar to Enbrel but not as costly because it is not as expensive to manufacture. It has the same mechanism of action, clinical effects, and safety profile as Enbrel.

Erelzi is considered a specialty drug; you will need to get it from a specialty pharmacy.

Drug Facts

Generic Name: Etanercept-szzs

Brand Name: Erelzi 

Drug Availability: Prescription

Therapeutic Classification: TNF inhibitor

Available Generically: No

Controlled Substance: N/A

Administration Route: Subcutaneous

Active Ingredient: Etanercept-szzs

Dosage Form: Injection

What Is Erelzi Used For?

The Food and Drug Administration (FDA) approved Erelzi to treat multiple autoimmune diseases, including:

How to Take Erelzi

You will receive your Erelzi injection once a week. Depending on why you're taking it, you may get an injection twice a week for a few months at first.

While it can be intimidating or scary to self-inject a medication, Erelzi comes with devices that make it easier. It is available in prefilled syringes or pen injectors. Neither of these requires you to attach needles or draw up liquid. A healthcare provider will show you how to inject the drug yourself until you are comfortable with the process.

The drug is given subcutaneously, which means the medicine is injected right under your skin instead of into a muscle or a vein. The needles are small, only about a quarter of an inch long. You can use your thighs, stomach area, or upper arms for subcutaneous injections, as these areas commonly have the most fat. Do not inject into cut, tender, bruised, or scarred skin or through clothing.

To get ready for your dose, remove your Erelzi pen or syringe from the refrigerator. Let it come to room temperature for about 15 to 30 minutes before use. This will make injecting more comfortable. Have your sharps container handy. Do not try to warm the medicine up by shaking it or using any external heating source.

To administer Erelzi Sensoready Pen injection:

  1. Hold the pen injector in the middle. Look at the medicine through the small window to make sure the solution is clear to pale yellow. It’s normal to see small white particles in it, but do not use it if it’s cloudy or contains large lumps or flakes.
  2. Before injecting, wash your hands and clean the injection site area with an alcohol swab. Allow your skin to dry without blowing on it or touching it again.
  3. Once ready to inject, remove the pen cap by twisting it in the direction of the arrow. Do not try to put the cap back on. Use the pen within five minutes of removing the cap.
  4. Hold the pen against your skin at a 90-degree angle. Then, press down firmly and hold the pen against your skin until you hear a click. The first click indicates that the injection has started. Several seconds later, you’ll hear a second click, indicating that the injection is almost done.
  5. Check to ensure the green indicator fills the viewing window and stops moving.
  6. Lift the pen off your skin and place the entire pen into your sharps container.
  7. If you see any blood, you can lightly press a cotton ball over the injection site, but do not rub your skin.
  8. Keep track of where you inject each dose, as you’ll want to rotate sites each time you administer the drug.

To administer Erelzi prefilled syringe injection:

  1. Hold the syringe at the clear part where you can see the medicine. Take a quick look to make sure the solution is clear to pale yellow. It’s normal to see small white particles in it, but do not use it if it’s cloudy or has large lumps or flakes.
  2. Wash your hands and clean the area of skin you plan to inject with an alcohol swab. Allow your skin to dry without blowing on it or touching it again.
  3. Remove the needle cap with the needle pointing away from yourself. You may see a drop of liquid at the end of the needle. This is normal.
  4. Pinch a section of your skin between your thumb and other fingers, and insert the needle completely at about a 45-degree angle.
  5. Relax the hand that is pinching the skin and slowly push the plunger down all the way to inject the medicine. Hold the syringe in place for five seconds.
  6. Keep the plunger fully pressed down and carefully pull the needle straight out from the injection site.
  7. Carefully release the plunger, allowing the needle guard to cover the exposed needle.
  8. Place the entire syringe into your sharps container.
  9. If you see any blood, you can lightly press a cotton ball over the injection site, but do not rub your skin.
  10. Keep track of where you inject each dose, as you’ll want to rotate sites each time you administer the drug.


Store your Erelzi pens and prefilled syringes in the refrigerator (at temperatures between 36 F to 46 F). If needed, you can store pens and syringes at room temperature (68 F to 77 F) for up to 28 days. Erelzi must be discarded if kept outside the fridge for more than 28 days.

Store pens and syringes in their original cartons to protect the medicine from light. Don’t expose Erelzi to extremely hot or cold temperatures, such as by freezing it or leaving it in your car on a hot day.

You will likely get a sharps container with your medication. If not, call the specialty pharmacy or ask your local pharmacist about getting a sharps container so that you don’t have loose needles or medicine in your household garbage.

How Long Does Erelzi Take to Work?

You may start to see some symptom improvement from Erelzi within one to two weeks, although it may take three to six months to take effect fully. Let your healthcare provider know if your symptoms worsen or don’t improve after a few months.

What Are the Side Effects of Erelzi?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the FDA at or 1-800-FDA-1088.

Common Side Effects

These are the most common side effects of Erelzi. Notify your healthcare provider if you experience these side effects and think they are severe or do not go away:

  • Injection site reactions, such as mild pain, itching, or redness in the injection site
  • Upper respiratory bacterial and viral infections, such as sinusitis (sinus infections), pharyngitis (a sore throat), or influenza
  • Diarrhea
  • Rash or pruritus (itching)

Severe Side Effects

Call your healthcare provider immediately if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Severe side effects can include:

  • Infections: Since TNF blockers like Erelzi affect your immune system, you may be more vulnerable to various infections while using this medication. This may be especially true if you have a suppressed immune system or are a carrier of some viruses like hepatitis B or tuberculosis. Your healthcare provider should check for these infections before starting you on Erelzi.
  • Cancers: Erelzi may reduce the immune system's ability to fight cancerous cells. The risk is only slightly increased for certain types of cancer such as melanoma (skin cancer), lymphoma (cancer of the lymphatic system), and leukemia (blood cancer). Discuss this risk and any concerns you have with your healthcare provider. For many, the potential benefits of Erelzi will outweigh a slight increase in cancer risk.
  • Heart failure: There have been some reports of worsening congestive heart failure (CHF) in people taking Erelzi, as well as some rare reports of new-onset CHF. Discuss any known heart issues with your healthcare provider.
  • Psoriasis: People using etanercept have developed new psoriasis or worsening of psoriasis. Call your healthcare provider if you notice any changes to your skin, such as red scaly patches, itching, cracking, or dryness.
  • Allergic reaction: Contact a healthcare provider immediately if you start to develop symptoms of an allergic reaction. Call 911 if your symptoms feel life-threatening. An allergic reaction can cause a severe rash, swollen face, or trouble breathing.
  • Autoimmune reactions: Erelzi can cause autoimmune reactions, such as lupus-like syndrome and autoimmune hepatitis (when your immune system attacks your liver).

Report Side Effects

Erelzi may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much Erelzi Should I Take?

Drug Content Provided and Reviewed by IBM Micromedex®

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For injection dosage form (prefilled syringe or Sensoready® pen):
    • For ankylosing spondylitis:
      • Adults—50 milligrams (mg) injected under the skin once a week.
      • Children—Use and dose must be determined by your doctor.
    • For juvenile idiopathic arthritis:
      • Children 2 years of age and older weighing 63 kilograms (kg) or more—50 milligrams (mg) injected under the skin once a week.
      • Children younger than 2 years of age or weighing less than 63 kg—Use and dose must be determined by your doctor.
    • For rheumatoid arthritis and psoriatic arthritis:
      • Adults—50 milligrams (mg) injected under the skin once a week with or without methotrexate.
      • Children—Use and dose must be determined by your doctor.
    • For plaque psoriasis:
      • Adults—At first, 50 milligrams (mg) injected under the skin two times a week for 3 months. Then, a maintenance dose of 50 mg injected under the skin once a week. Some patients may receive a starting dose of 25 or 50 mg per week.
      • Children 4 years of age and older weighing 63 kilograms (kg) or more—50 mg injected under the skin once a week.
      • Children younger than 4 years of age or weighing less than 63 kg—Use and dose must be determined by your doctor.


Due to the possible effects of this medication, there may be changes to how it is used. Therefore, users need to be aware of the following factors when taking Erelzi:

  • Pregnancy: There is not enough data regarding using Erelzi in pregnant people to confirm any risk of congenital disabilities, miscarriage, or adverse outcomes. The drug can be transferred to the fetus during pregnancy in small amounts via the placenta, but the effects of this are not well established. Speak with your healthcare provider about whether to use Erelzi if you plan to become pregnant.
  • Breastfeeding: Limited data has shown that Erelzi is present in human milk in small amounts. A breastfed baby would likely absorb a small amount of the drug. The effects this may have are unknown due to a lack of data. As in pregnancy, the clinical benefit of Erelzi for the nursing individual should be weighed against any risk the drug or the autoimmune condition may pose to a newborn.
  • Age: Erelzi is approved to treat pJIA in children 2 and older. It hasn’t been studied in children younger than 2. Its safety and effectiveness in that population are unknown. No differences in side effects were seen between younger and older adults (65 years and older). However, not enough older adults were included in clinical trials to know if they may be affected differently.

Missed Dose

You will most likely use Erelzi either once per week or twice per week. Make sure you understand how often you’re supposed to give an injection. It can help to set phone or calendar reminders for your doses.

If you forget to use Erelzi, inject your dose as soon as you remember, then take your next dose at your normally scheduled time. Ask your healthcare provider or a pharmacist if you’re not sure when to inject.

Overdose: What Happens If I Take Too Much Erelzi?

You are unlikely to accidentally overdose on Erelzi. The doses are pre-filled in one or two pens or syringes to administer each week. Keep track of where you inject and try to administer your doses regularly, around the same times each week.

What Happens If I Overdose on Erelzi?

If you think you or someone else may have overdosed on Erelzi, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Erelzi, call 911 immediately.


Drug Content Provided and Reviewed by IBM Micromedex®

It is very important that your doctor check the progress of you or your child at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Your body's ability to fight infection may be reduced while you are being treated with etanercept-szzs. It is very important that you call your doctor at the first signs of any infection. Check with your doctor right away if you or your child have fever, chills, cough or hoarseness, flu-like symptoms, lower back or side pain, painful or difficult urination, or unusual tiredness or weakness.

You or your child will need to have a skin test for tuberculosis before starting this medicine. Tell your doctor if you or anyone in your home has ever had a positive reaction to a tuberculosis skin test.

A small number of people (including children and teenagers) who have used this medicine have developed certain types of cancer (eg, leukemia, lymphoma, skin cancer). Talk with your doctor if you or your child have unusual bleeding, bruising, or weakness, swollen lymph nodes in the neck, underarms, or groin, or unexplained weight loss. Also, check with your doctor right away if your or your child's skin has red, scaly patches, or raised bumps that are filled with pus.

Serious nervous system problems, including Guillain-Barré syndrome, multiple sclerosis, demyelinating disease, and seizures have occurred rarely in people using this medicine. Talk with your doctor if you have concerns about this.

Check with your doctor right away if you have trouble breathing, swelling of the face, fingers, feet, or lower legs, or sudden weight gain. These may be signs of a heart condition called congestive heart failure.

This medicine may cause serious allergic reactions, including anaphylaxis, which can be life-threatening and requires immediate medical attention. Check with your doctor right away if you or your child have a rash, itching, swelling of the face, tongue, and throat, trouble breathing or swallowing, or chest pain after you receive the medicine.

Serious skin reactions can occur during treatment with this medicine. Check with your doctor right away if you or your child have blistering, peeling, or loosening of the skin, chills, cough, diarrhea, fever, itching, joint or muscle pain, red skin lesions, sore throat, sores, ulcers, or white spots in your mouth or lips, or unusual tiredness or weakness.

While you are being treated with etanercept-szzs, do not have any immunizations (vaccines) without your doctor's approval. Your child's vaccines need to be current before he or she begins using etanercept-szzs. Be sure to ask your child's doctor if you have any questions about this.

This medicine may increase your risk of having a lupus-like syndrome or autoimmune hepatitis. Check with your doctor right away if you or your child have fever or chills, a general feeling of discomfort, illness, or weakness, light-colored stools, nausea and vomiting, upper right-sided abdominal or stomach pain, or yellow eyes and skin.

Do not take other medicines unless they have been discussed with your doctor. This includes abatacept (Orencia®), anakinra (Kineret®), or cyclophosphamide (Cytoxan®). Using any of them together with this medicine may increase your risk of having serious side effects.

What Are Reasons I Shouldn't Take Erelzi?

You may not be able to take Erelzi if any of the following apply to you:

  • Neurological disorders: Central or peripheral nervous system demyelinating disorders, such as multiple sclerosis, optic neuritis, Guillain-Barré syndrome, and peripheral neuropathies may be worsened by Erelzi.
  • Infection: If you have an active, chronic, or recurrent infection of any organ or if you have sepsis, you should wait until the infection has cleared to start taking Erelzi.
  • Congestive heart failure (CHF): Rarely new-onset CHF occurs in people taking Erelzi even without preexisting heart disease. However, if you already have existing heart failure, you and your healthcare provider should discuss any increased risk and establish a plan for monitoring your heart disease carefully.
  • Wegener's Granulamatosis: Erelzi is not recommended in people with Wegener's Granulomatosis (a rare blood vessel disease) receiving immunosuppressive treatment.

What Other Medications Interact With Erelzi?

Some medications may interact with Erelzi; you may need to avoid certain medications or require additional monitoring if taking potentially interacting substances. Share all medications, both over-the-counter (OTC) and prescription, vitamins, and herbal supplements, with your healthcare team.

The following interactions can occur with Erelzi:

  • Live vaccines: Live vaccines include chickenpox (varicella), FluMist (flu vaccine nasal spray), MMR (measles, mumps, rubella), yellow fever vaccine, and some others. Let anyone who may be giving you a vaccine know that you take Erelzi. Non-live or inactivated vaccinations are fine.
  • Kineret (anakinra): Taking Erelzi simultaneously with anakinra, another drug used to treat rheumatoid arthritis by suppressing the immune system, can increase your risk of severe infections compared with Erelzi alone.
  • Orencia (abatacept): Taking abatacept with Erelzi can increase the risk of serious side effects, including infections.
  • Cyclophosphamide: This medication is used to treat several types of cancer, including breast cancer, lymphomas and leukemias. Taking this drug with Erelzi is not recommended because it can increase your risk for certain types of cancer.
  • Sulfasalazine: In a clinical study, people taking sulfasalazine and etanercept showed more significant decreases in neutrophil count than those taking etanercept alone. It’s not known exactly how significant this difference is. Low neutrophil count (neutropenia) can cause your body to heal slowly and make you more susceptible to infections.

What Medications Are Similar?

Other biologic and biosimilar medications similar to Erelzi exist. Some have slightly different mechanisms of action but are similar in that they mimic or improve a certain part of the immune system's functioning:

  • Enbrel (etanercept) is the biologic drug for which Erelzi is a biosimilar, also referred to as the reference product. Although highly similar to Erelzi, it is often a more expensive option.
  • Eticovo (etanercept-ykro) is another biosimilar for Enbrel.
  • Humira (adalimumab) is another biologic drug that is also a TNF inhibitor. It is used to treat two forms of inflammatory bowel disorder (IBD), Crohn’s disease and ulcerative colitis, both autoimmune diseases that affect the digestive system.
  • Remicade (infliximab) is given intravenously rather than subcutaneously every eight weeks in an infusion clinic. Biosimilars for Remicade include Avsola (infliximab-axxq), Inflectra (infliximab-dyyb), Ixifi (infliximab-qbtx) and Renflexis (infliximab-abda).
  • Cimzia (certolizumab pegol), another biologic drug, is used to treat many autoimmune conditions. No biosimilars exist for Cimzia.
  • Simponi (golimumab) is a monoclonal antibody injected subcutaneously. It’s also available as Simponi Aria, which is given intravenously at an infusion clinic. No biosimilars exist for Simponi.

This is a list of drugs also prescribed for immune-mediated conditions such as arthritis, digestive issues, or skin conditions. It is NOT a list of drugs recommended to take with Erelzi. In fact, you should not take these drugs together. Talk to your pharmacist or healthcare provider if you have any questions or concerns.

Frequently Asked Questions

  • What is Erelzi used for?

    Erelzi is an injectable medicine used to treat several types of autoimmune diseases including different types of rheumatoid arthritis and psoriasis. Erelzi is a biosimilar product for Enbrel, a more expensive biologic medicine.

  • How does Erelzi work?

    Erelzi is a TNF inhibitor, or tumor necrosis factor inhibitor. Too much of the TNF protein causes inflammation and joint damage, like in rheumatoid arthritis and other autoimmune conditions. Erelzi blocks the activity of this protein, decreasing inflammation.

  • What drugs should not be taken with Erelzi?

    Avoid live vaccinations while taking Erelzi, such as the chickenpox vaccine, FluMist (nasal spray flu vaccine), and MMR (measles, mumps, rubella) vaccines. Other medications to avoid are anakinra and sulfasalazine. These drugs taken with Erelzi can increase your risk for infection more than taking Erelzi alone. Cyclophosphamide taken with Erelzi can increase your risk for certain types of cancer.

  • Is Erelzi less effective than Enbrel?

    No, Erelzi is just as effective and safe as Enbrel. Erelzi is a biosimilar to Enbrel. A biosimilar is a biological drug highly similar to its reference product (the original drug). The FDA conducts rigorous evaluation and testing to ensure no clinically meaningful differences in safety and effectiveness between the biosimilar and the reference product. Therefore, you should not be concerned about using a biosimilar medication if it is prescribed to you.

How Can I Stay Healthy While Taking Erelzi?

Autoimmune diseases are difficult to understand because of our complex immune systems. Uncontrolled rheumatoid arthritis and skin conditions like psoriasis can profoundly impact your everyday life and be frustrating to deal with.

Fortunately, the advancement of drugs called monoclonal antibodies have made enormous differences in treating many conditions such as cancer, arthritis, asthma, and gastrointestinal conditions like Crohn’s disease and ulcerative colitis, and skin conditions like psoriasis and eczema.

Although it may seem scary to have to inject a medication yourself, subcutaneous injections are very easy, quick, and cause little to no pain. Remember to be patient and stick to your dosing schedule while also taking your other prescribed medications. This will help you manage your condition and its symptoms.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended as a replacement for medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration. Erelzi package insert.

  2. Food and Drug Administration. Biological product definitions.

  3. Boyman O, Comte D, Spertini F. Adverse reactions to biologic agents and their medical management. Nat Rev Rheumatol. 2014;10(10):612-27. doi:10.1038/nrrheum.2014.123

  4. Castelli MS, McGonigle P, Hornby PJ. The pharmacology and therapeutic applications of monoclonal antibodies. Pharmacol Res Perspect. 2019;7(6):e00535. doi:0.1002/prp2.535

  5. Food and Drug Administration. What is a biosimilar?

By Sara Hoffman, PharmD
Sara is a clinical pharmacist that believes everyone should understand their medications, and aims to achieve this through her writing.