Peginterferon Alfa-2a

This information from Lexicomp^® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Pegasys

Brand Names: Canada

Pegasys

What is this drug used for?

• It is used to treat hepatitis B and C infections.
• This drug may be used with other drugs to treat your health condition. If you are also taking other drugs, talk with your doctor about the risks and side effects that may happen.

What do I need to tell my doctor BEFORE I take this drug?

• If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
• If you have ever had any of these health problems: Autoimmune hepatitis, heart disease, or liver disease.
• If you have any of these health problems: High blood sugar (diabetes), low blood sugar, or thyroid problems.
• If you have had an organ transplant.
• If the patient is a newborn or infant. This drug has benzyl alcohol in it. If possible, avoid products with benzyl alcohol in newborns or infants. Serious side effects can happen in these children with some doses of benzyl alcohol, including if given with other drugs that have benzyl alcohol.

This is not a list of all drugs or health problems that interact with this drug.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take this drug?

• Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
• Avoid driving and doing other tasks or actions that call for you to be alert until you see how this drug affects you.
• Tell your doctor if you have signs of high or low blood sugar like breath that smells like fruit, dizziness, fast breathing, fast heartbeat, feeling confused, feeling sleepy, feeling weak, flushing, headache, unusual thirst or hunger, passing urine more often, shaking, or sweating.
• Low blood cell counts have happened with this drug. If blood cell counts get very low, this can lead to bleeding problems, infections, or anemia. Call your doctor right away if you have signs of infection like fever, chills, or sore throat; any unexplained bruising or bleeding; or if you feel very tired or weak.
• Avoid drinking alcohol while taking this drug.
• Severe and sometimes deadly pancreas problems (pancreatitis) have happened with this drug. Call your doctor right away if you have severe stomach pain, severe back pain, or severe upset stomach or throwing up.
• A severe skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause severe health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
• Some people have had lung problems with this drug. Sometimes, this has been deadly. Call your doctor right away if you have signs of lung problems like shortness of breath or other trouble breathing, cough that is new or worse, or fever.
• This drug may cause eye problems that may lead to loss of eyesight or blindness. Tell your doctor if you have or have ever had eye problems. Call your doctor right away if you have any changes in eyesight.
• It is not known if this drug will prevent liver failure or other liver problems like cancer. Talk with the doctor.
• This drug does not stop the spread of hepatitis to others through blood, body fluids, or having sex. Do not have any kind of sex without using a condom. Do not share injection equipment like needles. Do not share personal items that can have blood or body fluids on them like toothbrushes or razors. Talk with your doctor or other health care provider about safe sex and other ways to prevent spreading hepatitis to others.
• This drug may affect growth in children and teens in some cases. They may need regular growth checks. Talk with the doctor.
• This drug caused fertility problems in animals. It is not known if it will cause fertility problems in humans. Talk with the doctor.
• This drug may cause harm to an unborn baby. A pregnancy test will be done before you start this drug to show that you are NOT pregnant.
• If you may become pregnant, you must use birth control while taking this drug. If you get pregnant, call your doctor right away.
• Tell your doctor if you are breast-feeding. You will need to talk about any risks to your baby.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
• Signs of depression, suicidal thoughts, emotional ups and downs, abnormal thinking, anxiety, or lack of interest in life.
• Signs of high blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
• Signs of thyroid problems like change in weight; feeling nervous, excitable, restless, or weak; hair thinning; depression; eye or neck swelling; not able to focus; trouble with heat or cold; menstrual changes; shakiness; or sweating.
• Chest pain or pressure, a fast heartbeat, or an abnormal heartbeat.
• Shortness of breath, a big weight gain, or swelling in the arms or legs.
• Weakness on 1 side of the body, trouble speaking or thinking, change in balance, drooping on one side of the face, or blurred eyesight.
• Memory problems or loss.
• Not able to focus.
• A burning, numbness, or tingling feeling that is not normal.
• Severe and sometimes deadly liver problems have happened with this drug. Call your doctor right away if you have signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
• Severe bowel problems (colitis) have happened within 12 weeks of treatment with alpha interferons like this drug. Sometimes, this could be deadly. Call your doctor right away if you have severe stomach pain, bloody diarrhea, throwing up blood, or throw up that looks like coffee grounds.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Flu-like signs. These include headache, weakness, fever, shakes, aches, pains, and sweating.
• Diarrhea, stomach pain, upset stomach, throwing up, or decreased appetite.
• Dry mouth.
• Back, muscle, or joint pain.
• Feeling dizzy, tired, or weak.
• Hair loss.
• Trouble sleeping.
• Irritation where the shot is given.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to your national health agency.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

How is this drug best taken?

Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.

All products:

• It is given as a shot into the fatty part of the skin on the top of the thigh or the belly area.
• The shot is most often given once a week.
• If you will be giving yourself the shot, your doctor or nurse will teach you how to give the shot.
• Wash your hands before and after use.
• Do not shake.
• Do not use if the solution is cloudy, leaking, or has particles.
• This drug is colorless to a faint yellow. Do not use if the solution changes color.
• Move the site where you give the shot with each shot.
• Do not give into skin near the belly button or waistline.
• Throw away needles in a needle/sharp disposal box. Do not reuse needles or other items. When the box is full, follow all local rules for getting rid of it. Talk with a doctor or pharmacist if you have any questions.
• Drink lots of noncaffeine liquids unless told to drink less liquid by your doctor.
• Have your blood work checked and eye exams as you have been told by your doctor.
• Check your blood sugar as you have been told by your doctor.

Vials:

• Before giving the shot, warm the drug by rolling it in the palms of your hands for about 1 minute.
• Throw away any part of the opened vial not used after the shot is given.

Prefilled syringes:

• Before giving the shot, let it come to room temperature. Do not heat this drug.
• If you see foam in the solution, put the prefilled syringe back in the refrigerator to use at another time.
• Throw syringe away after use. Do not use the same syringe more than one time.

What do I do if I miss a dose?

• Take a missed dose as soon as you think about it and go back to your normal time.
• Do not take 2 doses at the same time or extra doses.
• If you miss your dose by more than 2 days, call your doctor to find out what to do.

How do I store and/or throw out this drug?

• Store in a refrigerator. Do not freeze.
• Throw away unopened drug if left at room temperature for more than 24 hours.
• Protect from light.
• Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
• Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

• If your symptoms or health problems do not get better or if they become worse, call your doctor.
• Do not share your drugs with others and do not take anyone else’s drugs.
• Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
• This drug comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time this drug is refilled. If you have any questions about this drug, please talk with the doctor, pharmacist, or other health care provider.
• If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2024-01-03

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