Pegvaliase injection

Pegvaliase is an injection that providers use to lower phenylalanine levels in people with phenylketonuria. Phenylketonuria (PKU) is a genetic condition where levels of phenylalanine (an amino acid) build up. If left untreated, phenylketonuria can affect a person’s cognitive development.

What is this medication?

PEGVALIASE (peg VAL i ase) works to lower phenylalanine levels in the blood. It is used with a special diet to treat phenylketonuria. This medicine is not a cure.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.



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What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • an unusual or allergic reaction to pegvaliase, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medication?

This medicine is for injection under the skin. Follow the directions on the prescription label. You will be taught how to give this medicine. Use exactly as directed. Take your medicine at the prescribed intervals. Do not take your medicine more often than directed.

It is important that you put your used needles and syringes in a special sharps container. Do not put them in a trash can. If you do not have a sharps container, call your pharmacist or healthcare provider to get one.

A special MedGuide will be given to you before each treatment. Be sure to read this information carefully each time.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.


What if I miss a dose?

If you miss a dose, take the next dose as scheduled. Do not take double or extra doses.

What may interact with this medication?

  • medroxyprogesterone acetate injection (used for birth control or hormone treatment)

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.


What should I watch for while using this medication?

Visit your doctor or health care professional for regular checks on your progress. Your condition will be monitored carefully while you are receiving this medicine. You will need blood work done while you are taking this medicine.

Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse.

You will need to be on a special diet while you are taking this medicine. Talk with your health care professional before making any changes to your diet.

If you have a severe allergic reaction during treatment, you will need to receive an auto-injection of epinephrine immediately. Get emergency medical help right away. Your healthcare provider may recommend that someone be with you when you give your injection, and for at least 1 hour after your injection to watch you for a severe allergic reaction. They may need to give you an injection of epinephrine and call for emergency medical help if a severe reaction occurs.

What side effects may I notice from receiving this medication?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • breathing problems
  • chest pain or chest tightness
  • confusion
  • fast, irregular heartbeat
  • joint pain
  • loss of control of urine or stools
  • redness, blistering, peeling or loosening of the skin, including inside the mouth
  • signs and symptoms of low blood pressure like dizziness; feeling faint or lightheaded, falls; unusually weak or tired
  • vomiting

Side effects that usually do not require medical attention (report these to your doctor or health care professional if they continue or are bothersome):

  • cough
  • diarrhea
  • hair loss
  • headache
  • nausea
  • pain, redness, or irritation at site where injected
  • sore throat
  • stomach upset or pain
  • tiredness

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children.

Store in a refrigerator between 2 and 8 degrees C (36 and 46 degrees F). Do not freeze. Keep this medicine in the original container. Throw away any unused medicine after the expiration date on the label.

If needed, you may also store at room temperature between 68 and 77 degrees F (20 and 25 degrees C) for up to 30 days. If taken out of the refrigerator, do not put it back in the refrigerator. Throw away unused medicine after the 30 days have passed.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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