Use Neulasta Onpro Kit (Subcutaneous) exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed. Pegfilgrastim should not be given within 14 days before or 24 hours after you receive chemotherapy. Pegfilgrastim 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 pegfilgrastim 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 pegfilgrastim. 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 pegfilgrastim 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.