Description and Brand Names

Drug information provided by: Merative, Micromedex®

US Brand Name

  1. Pegasys
  2. Pegasys Proclick

Descriptions


Peginterferon alfa-2a injection is used alone or together with other medicines (eg, ribavirin)to treat chronic hepatitis C infection in patients who are not able to take other medicine. It is also used to treat chronic hepatitis B infection. Peginterferon alfa-2a is a synthetic (man-made) version of a substance that is normally produced in the body. It helps your immune system fight hepatitis infections.

This medicine is available only with your doctor's prescription.

This product is available in the following dosage forms:

  • Solution

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of peginterferon alfa-2a injection in children younger than 5 years of age to treat chronic hepatitis C infection or in children younger than 3 years of age to treat chronic hepatitis B infection. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of peginterferon alfa-2a injection in the elderly. However, elderly patients are more likely to have unwanted effects (eg, heart and blood vessel problems, flu-like symptoms, or nerve problems) or age-related kidney problems, which may require caution and an adjustment in the dose for patients receiving peginterferon alfa-2a.

Breastfeeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

  • Fezolinetant
  • Telbivudine

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Bendamustine
  • Clozapine
  • Levoketoconazole
  • Methotrexate
  • Theophylline
  • Triclabendazole

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

  • Methadone

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Anemia or
  • Bleeding problems, history of or
  • Chest pain or
  • Colitis (inflammation of the bowels) or
  • Depression, history of or
  • Diabetes or
  • Diabetic retinopathy (eye problem caused by diabetes) or
  • Eye or vision problems (eg, optic neuritis, retinopathy) or
  • Heart or blood vessel disease or
  • Heart rhythm problems (eg, arrhythmia), history of or
  • Hyperglycemia (high blood sugar) or
  • Hypertension (high blood pressure) or
  • Hypoglycemia (low blood sugar) or
  • Kidney disease, severe or
  • Lung disease (eg, pneumonia, sarcoidosis) or
  • Manic episodes (bipolar depression), history of or
  • Neutropenia (low white blood cells) or
  • Psoriasis (skin disease) or
  • Psychiatric problems, history of or
  • Rheumatoid arthritis or
  • Stroke, history of or
  • Systemic lupus erythematosus (immune system disorder) or
  • Thrombocytopenia (low blood platelet count) or
  • Thyroid disease—Use with caution. May make these conditions worse.
  • Infection (eg, bacteria, virus, or fungus)—May decrease your body's ability to fight an infection.
  • Liver disease (eg, cirrhosis, autoimmune hepatitis), severe—Should not be used in patients with these conditions.
  • Organ transplant (eg, liver)—Use of peginterferon alfa-2a alone or in combination with ribavirin has not been studied in patients with this condition.

Proper Use

A nurse or other trained health professional may give you this medicine. It is given as a shot under your skin in the thighs or stomach. It may sometimes be given at home to patients who do not need to be in the hospital or clinic. If you are using this medicine at home, your doctor or nurse will teach you how to prepare and inject the medicine. Be sure that you understand how to use the medicine.

This medicine comes with a Medication Guide and patient instructions. Read and follow the instructions carefully. Ask your doctor if you have any questions.

If you use this medicine at home, you will be shown the body areas where this shot can be given. Use a different body area each time you give yourself or your child a shot. Keep track of where you give each shot to make sure you rotate body areas. This will help prevent skin problems.

This medicine is available in 2 forms: vial and prefilled syringe.

To use the prefilled syringe:

  • Wash your hands with soap and water before and after using this medicine.
  • Check the liquid in the syringe. It should be clear and colorless to light yellow. Do not use it if it is cloudy or has particles in it. If there is foam, put it back in the refrigerator for later use.
  • Allow the syringe to warm to room temperature.
  • Remove and throw away the rubber cap from the tip of the syringe barrel.
  • With one hand, hold the syringe by the barrel. With your other hand, hold the needle close to the hub where the green needle cover connects to the syringe.
  • Push the needle onto the syringe and tighten by using an easy twisting motion in the direction of the arrow.
  • Pull the green needle cover back from the needle toward the syringe barrel. Do not remove it.
  • Hold the syringe and needle tightly. Gently rock the plastic needle shield back and forth for removal. Remove the plastic needle shield by pulling it straight off.
  • If you see large air bubbles in the syringe, hold the syringe with the needle pointing up and tap the syringe to bring air bubbles to the top. Press the plunger in slightly to push air bubbles out of the syringe.
  • Pinch the skin firmly between your thumb and forefinger. Hold the syringe like a pencil at a 45 to 90 degree angle to your skin. With a quick "dart-like" motion, push the needle into the skin as far as it will go.
  • Gently push the plunger rod all the way down until empty.

To use the vial:

  • Wash your hands with soap and water before and after using this medicine.
  • Check the liquid in the vial. It should be clear and colorless to slightly yellowish. Do not use it if it is cloudy or has particles in it.
  • Allow the vial to warm by gently rolling it in the palms of your hands for 1 minute. Do not shake.
  • Remove the plastic cap from the top of the vial. Clean the rubber stopper.
  • Remove the needle cap. Fill the syringe with air by pulling back on the plunger to the mark on the syringe barrel that matches the prescribed dose.
  • Hold the vial on a flat surface. Do not touch the cleaned rubber stopper. Push the needle straight down through the middle of the rubber stopper on the vial. Slowly inject all the air from the syringe into the air space above the solution. Do not inject air into the fluid.
  • Keep the needle in the vial. Turn the vial upside down. Slowly pull back on the plunger to fill the syringe with the medicine to the prescribed dose.
  • Do not remove the needle from the vial. Lay the vial and syringe on its side on your flat work surface until you are ready to inject.
  • If you see large air bubbles in the syringe, hold the syringe with the needle pointing up and tap the syringe to bring air bubbles to the top. Press the plunger in slightly to push air bubbles out of the syringe.
  • Pinch the skin firmly between your thumb and forefinger. Hold the syringe like a pencil at a 45 to 90 degree angle to your skin. With a quick "dart-like" motion, push the needle into the skin as far as it will go.
  • Gently push the plunger rod all the way down until empty.

Drink extra fluids while you are using this medicine. This will keep you well hydrated, especially during the early part of your treatment.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For injection dosage form (solution):
    • For hepatitis B:
      • Adults—Dose is based on body weight and must be determined by your doctor. The dose is usually 180 micrograms (mcg) injected under the skin once a week for 48 weeks. The medicine should be used on the same day each week and at about the same time.
      • Children 3 years of age and older—Dose is based on body weight and must be determined by your doctor. The dose is usually not more than 180 mcg injected under the skin once a week (same time and day each week) for 48 weeks. The length of time will be determined by your doctor.
      • Children younger than 3 years of age—Use and dose must be determined by your doctor.
    • For hepatitis C:
      • Adults—Dose is based on body weight and must be determined by your doctor. The dose is usually 180 micrograms (mcg) injected under the skin once a week for 48 weeks. The medicine should be used on the same day each week and at about the same time.
      • Children—Use and dose must be determined by your doctor.
    • For hepatitis C infection, in combination with ribavirin:
      • Adults—Dose is based on body weight and must be determined by your doctor. The dose is usually 180 micrograms (mcg) injected under the skin once a week (same time and day each week) together with oral ribavirin 2 times a day for 24 to 48 weeks. The length of time will be determined by your doctor.
      • Children 5 years of age and older—Dose is based on body weight and must be determined by your doctor. The dose is usually not more than 180 mcg injected under the skin once a week (same time and day each week) together with oral ribavirin 2 times a day for 24 to 48 weeks. The length of time will be determined by your doctor..
      • Children younger than 5 years of age—Use and dose must be determined by your doctor.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

If you miss a dose or forget to use your medicine and you are 1 or 2 days late, use it as soon as you can. If it has been more than 2 days since you were supposed to use the medicine, call your doctor for instructions.

Storage

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Store in the refrigerator. Do not freeze.

Do not leave this medicine out of the refrigerator for more than 24 hours. Do not freeze or shake. Protect it from light.

Throw away used needles in a hard, closed container where the needles cannot poke through. Keep this container away from children and pets.

Precautions

It is very important that your doctor check your or your child's progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Using this medicine together with ribavirin while you are pregnant can harm your unborn baby. These medicines may also cause birth defects if the father is using it when his sexual partner becomes pregnant. If a pregnancy occurs while you are using these medicines, tell your doctor right away.

A negative pregnancy test is needed for women who are of childbearing age before starting treatment with this medicine and ribavirin. Effective birth control must be used by male and female patients during treatment and for 6 months after the last dose. Female patients will need to have pregnancy tests every month during treatment and for 6 months after the last dose.

This medicine may cause some people to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. If you, your child, or your caregiver notice any of these side effects, tell your doctor right away.

This medicine may cause serious allergic reactions, including anaphylaxis or angioedema, which can be life-threatening and require immediate medical attention. Call your doctor right away if you have itching, hives, hoarseness, trouble breathing, trouble swallowing, or any swelling of the hands, face, or mouth while you are using this medicine.

Serious skin reactions can occur with this medicine. Check with your doctor right away if you have blistering, peeling, or loosening of the skin, fever or chills, hives or welts, red skin lesions, a severe skin rash or acne, or sores or ulcers on the skin while you are using this medicine.

This medicine will not keep you from giving hepatitis B or hepatitis C to other people.

This medicine combined with ribavirin can temporarily lower the number of white blood cells in your blood, which will increase the chance of getting an infection. It can also lower the number of platelets, which are necessary for proper blood clotting. If this occurs, there are certain precautions you can take, especially when your blood count is low, to reduce the risk of infection or bleeding:

  • If you can, avoid people with infections. Check with your doctor immediately if you think you are getting an infection or if you get a fever or chills, cough or hoarseness, lower back or side pain, or painful or difficult urination.
  • Check with your doctor immediately if you notice any unusual bleeding or bruising, black, tarry stools, blood in the urine or stools, or pinpoint red spots on your skin.
  • Be careful when using a regular toothbrush, dental floss, or toothpick. Your medical doctor, dentist, or nurse may recommend other ways to clean your teeth and gums. Check with your medical doctor before having any dental work done.
  • Do not touch your eyes or the inside of your nose unless you have just washed your hands and have not touched anything else in the meantime.
  • Be careful not to cut yourself when you are using sharp objects such as a safety razor or fingernail or toenail cutters.
  • Avoid contact sports or other situations where bruising or injury could occur.

Check with your doctor right away if you have sudden and severe stomach pain, chills, constipation, nausea, vomiting, fever, or lightheadedness. These could be symptoms of pancreatitis.

Check with your doctor right away if you have vision changes, including blurred vision, difficulty reading, or eye pain during or after treatment. This could be symptoms of a serious eye problem. Your doctor may want an eye doctor (ophthalmologist) to check your eyes.

Peginterferon alfa-2a used together with ribavirin may affect your child's growth. Your doctor may need to check your child's height and weight during and after treatment with these medicines.

This medicine may cause some people to become drowsy, dizzy, or less alert than they are normally. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

  1. Black, tarry stools
  2. chills
  3. cough
  4. discouragement
  5. feeling sad or empty
  6. fever
  7. irritability
  8. lack of appetite
  9. loss of interest or pleasure
  10. lower back or side pain
  11. painful or difficult urination
  12. pale skin
  13. sore throat
  14. tiredness
  15. trouble sleeping
  16. trouble concentrating
  17. ulcers, sores, or white spots in the mouth
  18. unusual bleeding or bruising
  19. unusual tiredness or weakness

Less common

  1. Bone pain
  2. chest pain, discomfort, or tightness
  3. confusion
  4. constipation
  5. depressed mood
  6. dizziness
  7. dry skin and hair
  8. fainting
  9. fast heartbeat
  10. feeling cold
  11. hair loss
  12. headache
  13. heart murmur
  14. hives
  15. hoarseness or husky voice
  16. lightheadedness
  17. muscle cramps and stiffness
  18. pale skin
  19. rapid, shallow breathing
  20. slowed heartbeat
  21. sneezing
  22. stomach pain
  23. troubled breathing with exertion
  24. weight gain

Incidence not known

  1. Accumulation of pus in the arms or legs
  2. blistering, peeling, loosening of the skin
  3. decreased urination
  4. diarrhea
  5. dry mouth
  6. increase in heart rate
  7. itching
  8. joint or muscle pain
  9. red, irritated eyes
  10. red skin lesions, often with a purple center
  11. seizures
  12. sunken eyes
  13. swollen, red, tender area of infection in the arms or legs
  14. thirst
  15. wrinkled skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  1. Back pain
  2. cracked, dry, scaly skin
  3. crusting, irritation, itching, or reddening of the skin
  4. fear
  5. feeling unusually cold, shivering
  6. hair loss or thinning of the hair
  7. muscle or joint pain
  8. nervousness
  9. numbness
  10. pain
  11. rash
  12. redness
  13. scarring
  14. soreness
  15. stinging
  16. swelling
  17. tenderness
  18. tingling
  19. ulceration
  20. vomiting
  21. warmth

Less common

  1. Belching
  2. blurred vision
  3. heartburn
  4. indigestion
  5. memory problems
  6. stomach discomfort or upset

Incidence not known

  1. Change of hearing
  2. loss of hearing

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Portions of this document last updated: April 01, 2024

Original article: https://www.mayoclinic.org/drugs-supplements/peginterferon-alfa-2a-subcutaneous-route/side-effects/DRG-20067318