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Generic name: peginterferon alfa-2bpeg-in-ter-FEER-on-AL-fa-too-bee ]
Brand names: PegIntron, Sylatron
Drug classes: Antineoplastic interferons, Antiviral interferons

Medically reviewed by Philip Thornton, DipPharm. Last updated on May 11, 2022.

What is Sylatron?

Sylatron is made from human proteins that help the body fight viral infections.

Sylatron is a prescription medicine that is used to prevent malignant melanoma (a kind of skin cancer) from coming back after it has been removed by surgery.

Sylatron should be started within 84 days of surgery to remove lymph nodes containing cancer.

It is not known if Sylatron is safe and effective in children less than 18 years of age.


You should not use Sylatron if you have autoimmune hepatitis or severe liver damage, or if you are allergic to any type of interferon alfa.

Do not use Sylatron if you are pregnant, or if you are a man and your sexual partner is pregnant. Use effective contraception during treatment and for at least 10 days after the final dose.

Sylatron may cause serious or fatal side effects, and can worsen a medical condition you already have. Call your doctor if you have symptoms such as mood or behavior changes, chest pain, fast heartbeats, trouble breathing, numbness or weakness, loss of coordination, fever, chills, a cough with mucus, burning when you urinate, or bloody diarrhea.

Tell your doctor about any new or worsening mood symptoms, such as feeling irritable, hostile, aggressive, depressed, or having thoughts about suicide or hurting yourself.

Before taking this medicine

You should not use Sylatron if:

When taking Sylatron with other medicine: To make sure all medicines are safe for you, tell your doctor about all your medical conditions, and if you are pregnant or breastfeeding.

You should not use Sylatronn if you are pregnant, or if you are a man and your sexual partner is pregnant.

Peginterferon alfa-2b can worsen a medical condition you already have. To make sure Sylatron is safe for you, tell your doctor if you have ever had:

You may need to have a negative pregnancy test before starting this treatment.

Peginterferon alfa-2b may harm an unborn baby. Use effective birth control to prevent pregnancy while using this medicine and for at least 10 days after your last dose. Tell your doctor if you become pregnant.

This medicine may affect fertility (ability to have children) in women. However, it is important to use birth control to prevent pregnancy because peginterferon alfa-2b can harm an unborn baby.

You should not use Sylatron if you are pregnant, or if you are a man and your sexual partner is pregnant.

It may not be safe to breastfeed while using Sylatron. Ask your doctor about any risk.

How should I use Sylatron?

Use Sylatron exactly as directed. Follow all directions on your prescription label and read all medication guides or instruction sheets.

Sylatron is injected under the skin, usually once per week. A healthcare provider may teach you how to properly use the medication by yourself.

Read and carefully follow any Instructions for Use provided with your medicine. Ask your doctor or pharmacist if you don't understand all instructions.

Prepare an injection only when you are ready to give it. Do not use if the medicine looks cloudy, has changed colors, or has particles in it. Call your pharmacist for new medicine.

Your doctor may recommend you take a fever-reducer medication at bedtime to help prevent flu-like symptoms. Use this medicine for as long as your doctor has prescribed.

Pay special attention to your dental hygiene and have regular dental exams while using Sylatron. Rinse your mouth well if you vomit at any time while using Sylatron.

You may need frequent medical tests.

Sylatron vials (bottles) should be stored at 25°C (77°F). Excursions are permitted between 15°-30°C (59-86°F). Do not freeze. Do not reuse a vial.

Use a needle and syringe only once and then place them in a puncture-proof "sharps" container. Follow state or local laws about how to dispose of this container. Keep it out of the reach of children and pets.

What happens if I miss a dose?

Call your doctor for instructions if you miss a dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include headache, extreme tiredness, muscle pain, fever, sore throat, trouble breathing, bruising or bleeding.

What should I avoid while using Sylatron?

Avoid coffee, tea, energy drinks, or other products that contain caffeine.

Using this medicine will not prevent you from passing hepatitis to other people. Follow your doctor's instructions about how to avoid passing the disease to another person.

Sylatron side effects

Get emergency medical help if you have signs of an allergic reaction to Sylatron: hives, or a rash that spreads and causes blistering and peeling; chest pain, anxiety, difficult breathing; swelling of your face, lips, tongue, or throat.

Tell your doctor right away if you have unusual changes in mood or behavior, such as: depression, irritability, feeling hostile or aggressive, hallucinations, thoughts about hurting yourself, or falling back into a previous pattern of drug addiction. These symptoms may occur during treatment and up to 6 months after your last dose.

Sylatron may cause serious or fatal side effects. Call your doctor at once if you have:

Common Sylatron side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Sylatron?

Sometimes it is not safe to use certain medicines at the same time. Some drugs can affect your blood levels of other drugs you use, which may increase side effects or make the medicines less effective.

Other drugs may affect peginterferon alfa-2b, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use.

More about Sylatron (peginterferon alfa-2b)

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Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Sylatron only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.