Avonex Pen

Generic name: Interferon Beta-1a Autoinjector and Prefilled Syringes (Avonex) [ in-ter-FEER-on-BAY-ta-won-aye ]
Brand names: Avonex, Avonex Pen
Drug class: Interferons

Medically reviewed by Drugs.com. Last updated on Mar 12, 2024.

Uses of Avonex Pen:

• It is used to treat MS (multiple sclerosis).

What do I need to tell my doctor BEFORE I take Avonex Pen?

• If you have an allergy to interferon beta-1a or any other part of Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)).
• If you are allergic to Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)); any part of Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.

This medicine may interact with other drugs or health problems.

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 Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)) 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 Avonex Pen?

• Tell all of your health care providers that you take Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)). This includes your doctors, nurses, pharmacists, and dentists.
• Have blood work checked as you have been told by the doctor. Talk with the doctor.
• Talk with your doctor before you drink alcohol.
• This medicine is not a cure for MS (multiple sclerosis). Stay under the care of your doctor.
• A lot of times, reactions happen where the shot was given. Sometimes, very bad reactions may happen. Check with your doctor if you have any reaction that bothers you or does not go away. Call your doctor right away if you have any break in the skin, color changes (blue or black), swelling, or drainage of fluid where the shot was given.
• Very bad health problems like thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) have happened with drugs like this one. Sometimes, this has been deadly. This has happened several weeks to years after starting treatment. Call your doctor right away if you feel very tired or weak or have any bruising or bleeding, change in balance, change in eyesight, change in how much urine is passed, dark urine, fever, pale skin, trouble speaking or thinking, weakness on 1 side of the body, or yellow skin or eyes.
• Heart failure has happened with Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)), as well as heart failure that has gotten worse in people who already have it. Tell your doctor if you have heart disease. Call your doctor right away if you have shortness of breath, a big weight gain, a heartbeat that is not normal, or swelling in the arms or legs that is new or worse.
• Liver problems have happened with Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)). Sometimes, this has been severe and has led to a liver transplant or death. If you have questions, talk with the doctor.
• Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

How is this medicine (Avonex Pen) best taken?

Use Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

• It is given as a shot into a muscle.
• Take as you have been told by your doctor. This medicine is not to be used every day. Be sure you know how to use Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)).
• If you will be giving yourself the shot, your doctor or nurse will teach you how to give the shot.
• Do not use if the solution is cloudy, leaking, or has particles.
• This medicine is colorless to a faint yellow. Do not use if the solution changes color.
• Do not give into skin that is irritated, bruised, red, infected, or scarred.
• If stored in a refrigerator, let Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)) come to room temperature before using it. Leave it at room temperature for at least 30 minutes. Do not heat Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)).
• Wash your hands before and after use.
• Move the site where you give the shot with each shot.
• Do not shake.
• Throw away any part left over after the dose is given.
• 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.

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 Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)) 2 days in a row.

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 or symptoms of depression, suicidal thoughts, emotional ups and downs, abnormal thinking, anxiety, or lack of interest in life.
• Signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
• Signs of thyroid problems like change in weight; feeling nervous, excitable, restless, or weak; hair thinning; depression; neck swelling; not able to focus; trouble with heat or cold; menstrual changes; shakiness; or sweating.
• Signs of a urinary tract infection (UTI) like blood in the urine, burning or pain when passing urine, feeling the need to pass urine often or right away, fever, lower stomach pain, or pelvic pain.
• Chest pain.
• Seizures.
• Very bad dizziness or passing out.
• Change in eyesight.
• Swollen gland.
• Low blood cell counts have happened with Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)). 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.

Related/similar drugs

What are some other side effects of Avonex Pen?

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. Mild pain drugs may help.
• Feeling dizzy, sleepy, tired, or weak.
• Upset stomach.
• Stomach pain.
• Back, muscle, or joint pain.
• Dry mouth.

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

If OVERDOSE is suspected:

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.

How do I store and/or throw out Avonex Pen?

• Store in a refrigerator. Do not freeze.
• If needed, you may store at room temperature for up to 7 days. Write down the date you take Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)) out of the refrigerator. If stored at room temperature and not used within 7 days, throw Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)) away.
• Protect from heat and 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.

Consumer Information Use and Disclaimer

• 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.
• This medicine comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)) is refilled. If you have any questions about Avonex Pen (interferon beta-1a autoinjector and prefilled syringes (avonex)), 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.

Biological Products Related to Avonex Pen

Find detailed information on biosimilars for this medication.

Further information

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

Medical Disclaimer