On this page · 9 sections

Neulasta Onpro Kit

Generic name: pegfilgrastim

Brand names: Fulphila, Fylnetra, Neulasta, Neulasta Onpro Kit, Nyvepria, Stimufend, Udenyca Prefilled Syringe, Ziextenzo

Last updated November 3, 2026 0 views
Share

What is Neulasta Onpro Kit?

Neulasta Onpro Kit is used to prevent neutropenia (a lack of certain white blood cells) that happens after chemotherapy.

Neulasta Onpro Kit is a type of protein that helps your body make more white blood cells to fight against infection.

Neulasta Onpro Kit may also be used for reasons not mentioned in this medication guide.

This section was rewritten for readability and reviewed for meaning.

Warnings

Follow all instructions on your medicine label and package. Inform each of your healthcare providers about all your medical conditions, allergies, and all medicines you take.

This section was rewritten for readability and reviewed for meaning.

Before taking this medicine

You should not use Neulasta Onpro Kit if you are allergic to Neulasta Onpro Kit or filgrastim (Neupogen).

Tell your doctor if you have ever had:

  • sickle cell disorder;
  • kidney disease;
  • acute myeloid leukemia;
  • radiation treatment;
  • myelodysplastic syndrome (also called "preleukemia"); or
  • a latex allergy.

If you are being treated with Fulphila and receiving radiation with or without chemotherapy for breast or lung cancer, you could develop a blood disorder or blood cancer (leukemia). Ask your doctor about this risk.

Tell your doctor if you are pregnant or breastfeeding.

This section was rewritten for readability and reviewed for meaning.

Neulasta Onpro Kit side effects

Get emergency medical help if you have signs of an allergic reaction: hives, skin rash, sweating, warmth or tingly feeling; dizziness, fast heartbeats; wheezing, difficulty breathing; swelling of your face, lips, tongue, or throat.

Capillary leak syndrome is a rare but serious side effect of pegfilgrastim. Call your doctor right away if you have signs of this condition, which may include: decreased urination, tiredness, dizziness or light-headed feeling, trouble breathing, and sudden swelling, puffiness, or feeling of fullness.

Neulasta Onpro Kit may cause serious side effects. Call your doctor at once if you have:

  • sudden or severe pain in your left upper stomach spreading up to your shoulder;
  • sudden and severe pain in your chest, stomach, or back;
  • severe or ongoing pain anywhere in your body;
  • fever, tiredness;
  • shortness of breath, rapid breathing;
  • easy bruising, unusual bleeding, purple or red spots under your skin;
  • bruising, swelling, or a hard lump where the medicine was injected; or
  • kidney problems--little or no urination, pink or dark urine, swelling in your face or lower legs.

Your cancer treatments may be delayed or permanently discontinued if you have certain side effects.

Common side effects of Neulasta Onpro Kit may include:

  • bone pain; or
  • pain in your arms or legs.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

This section was rewritten for readability and reviewed for meaning.

How should I use Neulasta Onpro Kit?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed. Neulasta Onpro Kit should not be given within 14 days before or 24 hours after you receive chemotherapy.

Neulasta Onpro Kit is injected under the skin. A healthcare provider may teach you how to properly use the medication by yourself.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don't understand all instructions.

Prepare your injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

Your blood may need to be tested often.

Carefully follow your doctor's instructions when giving Neulasta Onpro Kit to a child who weighs less than 99 pounds (45 kilograms). The correct dose for a child this size cannot be accurately measured using the prefilled syringe.

You may need medical tests to help your doctor determine how long to treat you with Neulasta Onpro Kit.

Store the prefilled syringe in its original package in the refrigerator, protected from light. Do not shake or freeze.

Take the syringe out of the refrigerator and let it reach room temperature for 15 to 30 minutes before injecting your dose. If a syringe has become frozen, thaw it in a refrigerator. Do not use any syringe that has been frozen more than one time.

Do not use a Neulasta or Udenyca syringe that has been left at room temperature for longer than 48 hours. Do not use a Fylnetra, Fulphila, o Stimufend syringe that has been left at room temperature for longer than 72 hours. Do not use a Ziextenzo syringe that has been left at room temperature for longer than 5 days.

The Neulasta Onpro Injector is a special device placed on the skin that delivers your Neulasta Onpro Kit dose at a specific time. You will need to wear the device for 27 hours before the dose begins. The timed dose will then be released from the device slowly over a 45-minute period.

Keep Neulasta Onpro refrigerated until you are ready to wear it. Do not use an Neulasta Onpro device that has been left out of a refrigerator for longer than 12 hours. Do not use Nyvepria prefilled syringe that has been left out of the refrigerator for longer than 15 days.

While wearing Neulasta Onpro, you or a caregiver will need to check the device to make sure it is working properly.

Each prefilled syringe or Onpro Injector is for one use only. Throw it away after one use, even if there is still medicine left inside.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

What happens if I miss a dose?

Call your doctor for guidance if you miss an injection or if you experience an issue with the Neulasta Onpro Kit.

This section was rewritten for readability and reviewed for meaning.

What happens if I overdose?

Seek emergency medical help or call the Poison Help line at 1-800-222-1222.

Signs of an overdose include bone pain, pain while breathing, feeling short of breath when lying down, wheezing, struggling to breathe, coughing up foamy mucus, cold and clammy skin, anxiety, and fast heartbeats.

When using Neulasta Onpro: Do not travel, drive, or operate machinery while wearing the device.

This section was rewritten for readability and reviewed for meaning.

What other drugs will affect Neulasta Onpro Kit?

Other drugs may affect Neulasta Onpro Kit, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you begin or stop using.

Find detailed information on biosimilars for this medication.

This section was rewritten for readability and reviewed for meaning.

Common questions about Neulasta

Biosimilars vs Biologics: What are they and how do they compare?
A biosimilar is a biological product that is similar to a reference biologic (usually the originally approved product) and for which there are no clinically meaningful differences in terms of safety, purity, and potency. On Sept 25, 2026, the FDA approved Degevma (denosumab-adet), a biosimilar to Xgeva (denosumab), making it the most recently approved U.S. biosimilar. Continue reading
How do you increase white blood cells during chemo?
Your doctor may prescribe a medicine known as a colony stimulating factor to boost your white blood cell count if you are having chemotherapy ("chemo"). Chemo drugs work by killing rapidly growing cancer cells, but blood levels of white blood cells (known as neutrophils) may also decrease. Neutrophils help to fight infection in your body. Lower levels of these white blood cells can increase your risk for infection, especially during chemotherapy. Continue reading
What is the difference between Fulphila and Neulasta?
Fulphila (pegfilgrastim-jmbd) is a biosimilar to Neulasta (pegfilgrastim) and both are pegfilgrastim products. A biosimilar is highly similar to a biologic already approved by the FDA and has no clinically meaningful differences in terms of safety, purity and potency from the reference product (in this case Neulasta). Fulphila is expected to cost less than Neulasta, but does not come with the on-body-injector for home use like Neulasta. Continue reading
What is the difference between Udenyca and Neulasta?
Udenyca (pegfilgrastim-cbqv) and Neulasta (pegfilgrastim) are both biological drugs containing pegfligrastim. The US Food and Drug Administration (FDA) has approved Udencya as a biosimilar of Neulasta, which means it is "highly similar to, and has no clinically meaningful differences from" Neulasta - it is just as safe and effective and used in the same way. The two drugs, however, are not interchangeable. Continue reading
How is Fulphila injected / administered?
Fulphila (pegfilgrastim) prefilled syringe is injected into the area just under your skin (subcutaneous). It can be injected into the thigh, stomach area (abdomen), outer area of the upper arm, or the upper outer area of the buttocks. You or a caregiver may able to self-administer these injections after training from a healthcare provider. Continue reading
Is Fulphila a chemo drug?
No, Fulphila (pegfilgrastim-jmbd) is a biosimilar prescription medicine to Neulasta (pegfilgrastim) used to boost the number of white blood cells in cancer patients receiving chemotherapy ("chemo"). Fulphila is a man-made form of a protein known as a granulocyte colony-stimulating factor (G-CSF) used to help prevent neutropenia (low white blood cells) and possible infections due to chemotherapy. Continue reading
What does cbqv stand for in pegfilgrastim?
The “cbqv” suffix is found in the biosimilar name for Udenyca (pegfilgrastim-cbqv), a biologic drug used to prevent neutropenia (a lack of certain white blood cells) caused by receiving chemotherapy. The suffix is used to distinguish its name from the original reference product, in this case Neulasta (pegfilgrastim), which has no suffix. Continue reading

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
General medicine information Consumer-friendly language

Content is provided for education and is not medical advice. See our medical disclaimer.