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Pronunciation: peg-IN-ter-FEER-on AL-fa too-ay
Common Brand Name(s): Pegasys
This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
This medication may rarely cause or worsen some serious medical conditions, including mental/mood problems (such as depression), autoimmune conditions (such as lupus, rheumatoid arthritis), blood vessel problems (such as heart disease), or infections. Careful monitoring by your doctor may decrease your risk. Tell your doctor right away if you develop any serious symptoms or side effects (see Side Effects section). Some side effects may go away or lessen after stopping treatment with this medication.
Peginterferon alfa-2a is used alone or in combination with other medications to treat chronic hepatitis B and chronic hepatitis C, viral infections of the liver. It works by decreasing the amount of hepatitis virus in the body and helps your body's natural defense (immune system) fight the infection. Chronic hepatitis infection can lead to serious liver damage (cirrhosis) and liver cancer.
It is not known if peginterferon can cure hepatitis B or hepatitis C infections or can prevent you from passing the virus to others. Practice "safer sex" (such as the use of latex condoms) to lower the risk of passing the virus to others.
Read the Medication Guide and Instructions for Use provided by your pharmacist before you start using peginterferon alfa-2a and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
If you are using this medication at home, learn all preparation and usage instructions from your health care professional and the product package. To increase comfort, remove this medication from the refrigerator and let it warm to room temperature as directed in the Instructions for Use. Do not warm up this medication in any other way such as heating in the microwave or placing in hot water. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.
Inject this medication under the skin in your abdomen or thigh as directed by your doctor, usually once every week. Do not inject near the belly button or at the waistline. Before injecting each dose, clean the injection site with rubbing alcohol. Change the injection site each time to lessen injury under the skin. Do not shake this medication. Doing so may make it work less well.
The dosage is based on your medical condition, lab tests, and response to treatment. In children, the dosage is also based on height and weight. Use this medication regularly to get the most benefit from it. To help you remember, use it at about the same time on the same day each week.
Drink plenty of fluids while using this medication unless your doctor directs you otherwise.
See also Warning section.
Most people have flu-like symptoms such as headache, tiredness, fever, chills, and muscle aches, but these usually decrease after the first few weeks of treatment. You can lessen these side effects by injecting this medicine at bedtime and using fever reducers/pain relievers such as acetaminophen before each dose. Ask your doctor or pharmacist for more information. Nausea, vomiting, diarrhea, dry mouth, loss of appetite, dizziness, trouble sleeping, or redness/swelling at the injection site may also occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Tooth and gum problems may sometimes occur during treatment. Having a dry mouth can worsen this side effect. Prevent dry mouth by drinking plenty of water or using a saliva substitute. Brush your teeth well at least twice a day and have regular dental exams. If you vomit, rinse your mouth afterward to lessen the chance of tooth and gum problems.
Temporary hair loss may occur. Normal hair growth should return after treatment has ended.
Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including:
Get medical help right away if you have any very serious side effects, including:
This drug may cause serious mental/mood changes that may get worse during treatment or after your last dose. Tell your doctor right away if you have symptoms such as confusion, depression, thoughts of suicide or hurting others, unusual irritability, or aggressive behavior.
This medication may lower your ability to fight infections. This may make you more likely to get a serious (rarely fatal) infection or make any infection you have worse. Tell your doctor right away if you have any signs of infection (such as sore throat that doesn't go away, fever, chills, cough).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before using peginterferon alfa-2a, tell your doctor or pharmacist if you are allergic to it; or to polyethylene glycol (PEG); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of:
This medication can make you more likely to get infections or may worsen any current infections. Avoid contact with people who have infections that may spread to others (such as chickenpox, measles, flu). Consult your doctor if you have been exposed to an infection or for more details.
Tell your health care professional that you are using peginterferon alfa-2a before having any immunizations/vaccinations. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose).
To lower the chance of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.
This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Children may be more sensitive to the side effects of this drug, especially mental/mood changes (such as severe depression, thoughts/attempts of suicide). Peginterferon may also slow down a child's growth. Normal weight gain and growth usually return after treatment is over, but the final adult height may be lower than expected. See the doctor regularly so your child's height and weight can be checked.
Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using peginterferon alfa-2a. Peginterferon alfa-2a may harm an unborn baby. Ask about reliable forms of birth control while using this medication. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.
Peginterferon alfa-2a, when used in combination with ribavirin, must not be used during pregnancy by either the pregnant woman or her male partner. The combination may harm an unborn baby. Reliable forms of birth control must be used whenever at least one sexual partner is using these medicines together. Female patients should continue using birth control for 9 months after stopping treatment. Male patients should continue using birth control for 6 months after stopping treatment. If you or your partner become pregnant, or if you think you or your partner may be pregnant, tell your doctor right away.
It is unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
A product that may interact with this drug is:
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center.
Do not share this medication with others.
Lab and/or medical tests (such as blood counts, thyroid tests, virus levels, kidney/liver function, triglyceride levels, eye exams) should be done before you start using this medication and while you are using it. Keep all medical and lab appointments.
Do not change brands of interferon without asking your doctor or pharmacist. Other interferons may not have the same effects on your disease.
If you miss a dose, use it as soon as you remember if it is within 2 days after your scheduled dose. Use your next dose on the day you usually use it. If more than 2 days have passed since your missed dose, ask your doctor or pharmacist right away for a new dosing schedule.
If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.
Store in the refrigerator away from light and moisture. Do not freeze. Do not leave out of the refrigerator for more than 24 hours. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised March 2022.
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