White cell growth factor injections after chemotherapy

This page is for people getting filgrastim (Neupogen) shots during chemotherapy. It explains what the shots do, when they are given, side effects to report, and when to get help.

Chemotherapy targets fast-dividing cells, and bone marrow is full of them. One thing that gets hit hard is the neutrophil, a white blood cell whose job is fighting infection. MedlinePlus states the link directly: doctors give filgrastim because chemotherapy can lower neutrophils.

Fewer neutrophils means weaker defense. So instead of just waiting for the marrow to catch up, an injection pushes production along faster. MedlinePlus describes filgrastim as a drug given to lower the chance of infection in people who have non-myeloid cancer and are getting chemotherapy.

You may know it by a brand name instead. MedlinePlus lists Neupogen, Granix, Nivestym, Releuko, and Zarxio among them.

Know your schedule before your cycle starts.

The timing is set by your oncology team and depends on your regimen. MedlinePlus says filgrastim is given 1 to 2 times a day depending on the condition being treated. Ask which day of your cycle the first shot is due and how many days you will have them. Filgrastim is not usually given right around the time of chemotherapy, so do not move, skip or double a shot on your own. Call your oncology team if you miss one or are unsure when to take it.

The injection schedule sits inside your chemo cycle instead of replacing part of it.

MedlinePlus describes filgrastim as a liquid that comes in vials and prefilled syringes. You get it as a shot under the skin, or through a vein. MedlinePlus says it is given 1 to 2 times a day, depending on the condition.

Some people get these shots at a clinic. Others learn to give the injection at home, or a family member does. If that applies to you, ask for a real demonstration, and get a phone number for when something feels wrong.

Filgrastim is not only a chemotherapy support drug. MedlinePlus also lists it for bone marrow transplant and severe chronic neutropenia. It is also used to increase the chance of survival in people exposed to harmful amounts of radiation.

Knowing that can be reassuring if you meet someone on the same injection for a completely different reason.

Bone pain is the one people ask about most, and it is a known effect. MedlinePlus lists bone and joint pain among the possible side effects. Tell your team about pain, especially if it is severe or does not go away.

Two facts matter together here. The injection lowers your infection risk, but it does not erase it. Whatever infection warning signs your team gave you still apply while you are on these injections. NCI's general guidance during cancer treatment is blunt: infections can be life threatening and need urgent medical attention. Call your health care team if you have signs of one.

If you are not sure whether something counts, call anyway. Your team would rather field a call about aching legs than miss the start of an infection.

Daily shots can be a real logistical task, not just a medical one. If a clinic is giving them, that means daily trips, which can be tiring on top of everything else treatment already demands. If you are giving them at home, keeping supplies stocked and storing the medicine correctly both matter.

MedlinePlus says most formulations need refrigeration, and some can stay out for a limited time. Ask your pharmacy how yours should be stored. Set a daily reminder so a dose is never missed by accident, especially on a day when you feel unwell and just want to rest.

MedlinePlus says to call your doctor immediately if any of these happen. It does not rank them, and neither should you. If you have a fever, use the temperature your team gave you as the call threshold (CDC uses 100.4 F).

• A rash, hives, itching, swelling of the face, eyes or mouth, wheezing, or shortness of breath.
• Fever together with shortness of breath, trouble breathing, or fast breathing.
• Coughing up blood. Treat this as an emergency: call 911 or go to the nearest emergency room.
• Pain in the upper left part of the stomach, or at the tip of the left shoulder.
• Fever with abdominal pain, back pain, or feeling tired or unwell.
• Swelling of the stomach area with decreased urination, trouble breathing, dizziness or tiredness.
• Unusual bleeding or bruising, purple marks under the skin, or red skin.
• Decreased urination, dark or bloody urine, or swelling of the face or ankles.
• Signs of infection, such as chills, cough, sore throat, mouth sores or cloudy or bloody urine. NCI lists these as signs to report.

If breathing is difficult, do not wait for a call back. That is an emergency, and the usual emergency number for your area is the right one to use.