How does this medication work? What will it do for me?
Peginterferon alfa-2a belongs to the class of medications known as interferons. It is used to treat chronic hepatitis B and chronic hepatitis C, which are diseases of the liver. Peginterferon alfa-2a works by helping the immune system fight the hepatitis B and C virus, and by making it harder for the virus to reproduce within the body.
This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.
Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are being given this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.
Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.
What form(s) does this medication come in?
180 µg/0.5 mL (prefilled syringe)
Each 0.5 mL of sterile, ready-to-use solution for subcutaneous injection contains 180 µg of peginterferon alfa-2a (expressed as the amount of interferon alfa-2a). Nonmedicinal ingredients: sodium chloride, 80 polysorbate, benzyl alcohol, sodium acetate trihydrate, acetic acid, and water for injection.
180 µg/mL (single use vial)
Each mL of sterile, ready-to-use solution for subcutaneous injection contains 180 µg of peginterferon alfa-2a (expressed as the amount of interferon alfa-2a). Nonmedicinal ingredients: sodium chloride, 80 polysorbate, benzyl alcohol, sodium acetate trihydrate, acetic acid, and water for injection.
180 µg/0.5 mL (ProClick™ Autoinjector)
Each mL of sterile, ready-to-use solution for subcutaneous injection contains 180 µg of peginterferon alfa-2a (expressed as the amount of interferon alfa-2a). Nonmedicinal ingredients: sodium chloride, 80 polysorbate, benzyl alcohol, sodium acetate trihydrate, acetic acid, and water for injection.
The ready-to-use autoinjector includes a post-injection needle shield designed to help prevent needle-stick injuries and keep the needle non-visible.
How should I use this medication?
The usual dose of peginterferon alfa-2a is 180 µg once weekly for a period of 48 weeks. If there is no improvement after 12 weeks of use, your doctor may stop the treatment. This medication is usually injected under the skin (subcutaneously) of the abdomen or thigh.
If you are giving yourself the injections, it is very important that you very carefully follow your health care professional's directions and the instructions included with the medication. After the medication has been mixed, it should be used right away. Needles and syringes should never be reused. All used needles and syringes should be put into a sharps container and kept out of the reach of children.
Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.
It is important to use this medication exactly as prescribed by your doctor.
If you miss a dose and remember within 2 days of the scheduled dose, give the dose as soon as possible. If more than 2 days have passed, check with your doctor for further instructions. Do not inject a double dose to make up for a missed one.
Store this medication in the refrigerator, protect it from light and moisture, and keep it out of the reach of children. Do not freeze or shake the medication. Do not use this medication if it is discoloured or has particles floating in it.
Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.
Who should NOT take this medication?
Do not use this medication if you:
- are allergic to peginterferon alfa-2a, or any ingredients of the medication
- are allergic to any other interferon, to E. coli-derived products, or polyethylene glycol
- have autoimmune hepatitis
- have a history of other autoimmune disease
- have decompensated cirrhosis
- have HIV-HCV (human immunodeficiency virus and hepatitis C virus) with cirrhosis and a baseline Child-Pugh score greater than or equal to 6
- have a history of a severe psychiatric condition
- have an uncorrected thyroid condition
- are breast-feeding
Do not give this medication to children less than 6 months of age.
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- back pain
- cough
- decreased desire for sexual activities
- diarrhea
- dry, itchy skin
- dry mouth
- fatigue
- flu-like symptoms (unusual tiredness, fever, chills, muscle aches, joint pain, and headaches)
- hair thinning
- loss of appetite
- nausea
- poor concentration
- rash
- redness, swelling, bruising, irritation, or itching at the site of the injection
- trouble sleeping
- vomiting
Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- anemia (paleness, tiredness, shortness of breath)
- bloody diarrhea
- changes in mood (e.g., irritability, anxiety, aggression)
- dizziness
- hallucinations (seeing or hearing things that are not there)
- high blood sugar (increased thirst, hunger, weakness, drowsiness, blurred vision, weight loss)
- loss of coordination
- low blood sugar (headache, hunger, weakness, irritability, trouble concentrating)
- lower back or side pain
- lung problems (e.g., difficulty breathing, pneumonia)
- numbness or tingling or burning sensations
- persistent cough
- signs of depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
- signs of infection (e.g., chills, fever, cough, sore throat, difficulty or painful urination, difficulty breathing)
- ulcers or sores in the mouth or throat
- unusual bruising or bleeding (e.g., bleeding gums, nosebleeds, blood in the urine, pinpoint-sized red spots on skin)
- vision changes (e.g., blurred vision, loss of vision)
- weakness
- worsening psoriasis
Stop taking the medication and seek immediate medical attention if any of the following occur:
- fast or irregular heartbeat (palpitations)
- severe skin rash (blistering, peeling, and spreading)
- suicidal feelings or suicide attempts
- symptoms of a heart attack (e.g., severe chest pain or pressure, pain in the arm or shoulder, nausea, sweating)
- symptoms of a severe allergic reaction (e.g., hives; difficulty breathing; swelling of the face, mouth, throat, or tongue)
- symptoms of a stroke (e.g., sudden and severe headache, sudden weakness or numbness in the arms or legs, sudden vision changes, sudden dizziness)
- trouble breathing
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Allergic reactions: In rare cases, this medication may cause severe allergic reactions. If you notice hives, swelling of the face or throat, or difficulty breathing, stop using this medication and get medical help immediately.
Autoimmune conditions: This medication may cause or worsen autoimmune conditions including myositis, hepatitis, immune thrombocytopenic purpura (ITP), rheumatoid arthritis, interstitial nephritis, thyroiditis, and systemic lupus erythematosus. If psoriasis appears, the medication may need to be discontinued.
Blood glucose (sugar): This medication can cause low or high blood sugar. People with diabetes should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you experience high blood sugar (increased thirst, hunger, weakness, drowsiness, blurred vision, weight loss) or low blood sugar (headache, hunger, weakness, irritability, trouble concentrating) while taking this medication, contact your doctor.
Blood problems: This medication may suppress bone marrow function and cause blood problems such as low platelet counts, low white blood cell counts, and anemia. Your doctor will monitor you for these problems with blood tests. If you experience persistent fever and chills, tiredness, shortness of breath, or easy bruising or bleeding, contact your doctor.
Colon disorders: This medication may cause certain types of colitis. Report any stomach or abdominal pain, bloody diarrhea, or fever to your doctor immediately.
Depression and other psychiatric conditions: This medication can cause depression and other psychiatric conditions. People with psychiatric conditions should be closely monitored by their doctor while using this medication, as it may worsen these conditions.
If you experience symptoms of depression such as poor concentration, changes in weight, changes in sleep, decreased interest in activities, or notice them in a family member who is taking this medication, contact your doctor as soon as possible.
Dizziness/reduced alertness: Peginterferon alfa-2a may affect the mental or physical abilities needed to drive or operate machinery. Avoid driving, operating machinery, or performing other hazardous tasks until you have determined how this medication affects you.
Eye disorders: Certain eye disorders have been observed in people using this medication. If you experience any changes in vision while taking this medication, contact your doctor.
Flu-like symptoms: This medication may cause a flu-like reaction with aching muscles, fever, chills, and headache. Your doctor may prescribe acetaminophen before each dose of this medication and as needed to help reduce these symptoms.
Fluids: This medication may cause dehydration. People taking this medication should drink adequate fluids, especially on hot days or when exercising.
Heart disease: This medication, as well as others like it, can cause heart problems such as high blood pressure, chest pain, heart attack, abnormal heart rhythms, and heart failure. If you have had a heart attack, heart failure, or changes in heart rhythm (arrhythmias), discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. People with severe, unstable, or uncontrolled heart disease should not use this medication.
Kidney disease: People with kidney disease should discuss with their doctor how this medication may affect their medical condition and whether any special monitoring is needed. People with reduced kidney function may require a lower dose.
Liver function: People who are taking this medication will need frequent checkups to test their liver function. People with reduced liver function may require a lower dose of the medication or may need to stop taking it.
Lung disorders: Certain lung disorders may occur in people using this medication, causing breathing difficulty. These conditions can be fatal. If you experience fever, cough, or shortness of breath, contact your doctor as soon as possible.
Pancreatitis: This medication may cause pancreatitis, which may be fatal. If you develop symptoms of pancreatitis (e.g., severe abdominal pain with or without vomiting), get immediate medical attention.
Stroke: This medication has been associated with strokes. If you experience symptoms of a stroke (e.g., sudden and severe headache, sudden weakness or numbness in the arms or legs, sudden vision changes, sudden dizziness) while taking this medication, get immediate medical attention.
Thyroid disorders: This medication can cause or worsen hypothyroidism (low thyroid) or hyperthyroidism (high thyroid). People with thyroid conditions should discuss with their doctor how this medication may affect their medical condition, how their medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Transplants: The safety and effectiveness of using this medication have not been established for people who have had a liver or other organ transplant.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately. Women who may become pregnant should use an effective method of birth control while using peginterferon alfa-2a.
Breast-feeding: It is not known if peginterferon alfa-2a passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children and adolescents: The safety and effectiveness of using this medication have not been established for children under the age of 18. This medication is not recommended for use by newborns or infants because peginterferon alfa-2a contains benzyl alcohol and may be harmful.
What other drugs could interact with this medication?
There may be an interaction between peginterferon alfa-2a and any of the following:
- aldesleukin
- BCG
- capecitabine
- clozapine
- deferiprone
- fluorouracil
- mesalamine
- methadone
- olaparib
- olsalazine
- ribavirin
- sulfasalazine
- theophyllines (aminophylline, theophylline)
- tizanidine
- warfarin
- zidovudine
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.
All material copyright MediResource Inc. 1996 – 2024. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/PEGASYS