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Pegaspargase Injection

pronounced as (peg as' par jase)

Why is this medication prescribed?

Pegaspargase is used with other chemotherapy drugs to treat a certain type of acute lymphocytic leukemia (ALL; a type of cancer of the white blood cells). Pegaspargase is also used with other chemotherapy drugs to treat a certain type of ALL in people who have had some types of allergic reactions to medications similar to pegaspargase such as asparaginase (Elspar). Pegaspargase is an enzyme that interferes with natural substances necessary for cancer cell growth. It works by killing or stopping the growth of cancer cells.

How should this medicine be used?

Pegaspargase comes as a liquid to be injected into a muscle or infused intravenously (into a vein) over 1 to 2 hours by a doctor or nurse in a medical office or hospital outpatient clinic. It is usually given not more often than once every 2 weeks. Your doctor will choose the schedule that will work best for you based on your response to the medication.

Ask your pharmacist or doctor for a copy of the manufacturer's information for the patient.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before receiving pegaspargase,

  • tell your doctor and pharmacist if you are allergic to pegaspargase, asparaginase (Elspar), any other medications, or any of the ingredients in pegaspargase injection. Ask your pharmacist or a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.
  • tell your doctor if you have or ever had pancreatitis (swelling of the pancreas), blood clots, or severe bleeding, especially if these happened during an earlier treatment with asparaginase (Elspar). Your doctor will probably not want you to receive pegaspargase.
  • tell your doctor if you are pregnant or plan to become pregnant. If you become pregnant while receiving pegaspargase, call your doctor.
  • tell your doctor if you are breast-feeding. You should not breast-feed during your treatment with pegaspargase.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What side effects can this medication cause?

Pegaspargase may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • nausea
  • vomiting
  • diarrhea
  • fever
  • tiredness
  • dizziness

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately:

  • hives
  • skin rash
  • itching
  • hoarseness
  • difficulty breathing or swallowing
  • headache
  • swelling of the face, arms, or legs
  • fainting
  • chest pain
  • ongoing pain that begins in the stomach area, but may spread to the back
  • frequent urination
  • increased thirst

Pegaspargase may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

  • rash

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to pegaspargase.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Oncaspar®

Other names

  • PEG-L-asparaginase
Last Revised - 12/15/2012