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Drug


Avonex
interferon beta 1a
 



Generic Name:interferon beta-1a
Pronounced:in ter FEAR on BAY tah 1a
Brand Names:Avonex, Rebif

What is the most important information I should know about interferon beta-1a?

Contact your doctor immediately or seek emergency medical attention if you begin feeling depressed or anxious or if you have thoughts of suicide.

What is interferon beta-1a?
Interferon beta-1a is a protein. Interferons are released in the body in response to viral infections. Interferons are important for fighting viruses in the body, regulating reproduction of cells, and regulating the immune system.
Interferon beta-1a is a specific interferon used in the treatment of relapsing multiple sclerosis to slow the development of physical disability and to decrease the frequency of exacerbations.
Interferon beta-1a may also be used for purposes other than those listed in this medication guide.

What should I discuss with my healthcare provider before using interferon beta-1a
Before using this medication, tell your doctor if you currently have or have had in the past
  • depression, suicidal thoughts, or anxiety;
  • epilepsy or another seizure disorder;
  • liver disease;
  • alcohol abuse;
  • thyroid problems;
  • blood problems such as easy bruising or bleeding, anemia (low red blood cells), or low white blood cells;
  • angina;
  • congestive heart failure; or
  • irregular heartbeats.
You may not be able to use interferon beta-1a, or you may require a dosage adjustment or special monitoring if you have any of the conditions listed above.
Interferon beta-1a is in the FDA pregnancy category C. This means that it is not known whether interferon beta-1a will harm an unborn baby. Interferon beta-1a may cause a miscarriage or spontaneous abortion.Do not use this medication if you are pregnant or could become pregnant during treatment.
It is not known whether interferon beta-1a passes into breast milk. Do not use this medication without first talking to your doctor if you are breast-feeding a baby.

How should I use interferon beta-1a?

Use interferon beta-1a exactly as directed by your doctor. If you do not understand these directions, ask your doctor, nurse, or pharmacist to explain them to you.
The Avonex formulation of interferon beta-1a is used as an intramuscular (into the muscle) injection. Avonex is usually prescribed for use once a week.
The Rebif formulation of interferon beta-1a is used as a subcutaneous (under the skin) injection. Rebif is usually prescribed for use three times a week. Rebif should be used on the same three days each week and doses should be 48 hours apart.
Your doctor or nurse will give you detailed instructions on how and where to inject the medication prescribed for you. Do not inject this medication if you are unsure how.
Once the Avonex solution is mixed, use it as soon as possible within 6 hours of mixing. If you do not inject it immediately, store it in the refrigerator for up to 6 hours. Do not allow the solution to freeze.
The Rebif solution is provided in prefilled syringes that should each be used to administer a single injection.. Always use a new, unopened prefilled syringe for each injection; never reuse a syringe.
It is important to rotate the site of injection with each dose to minimize the risk of an injection site reaction or damage to the tissue. Do not inject this medication into any site that is red, painful, or hard.
Do not inject interferon beta-1a if it is discolored or has particles in it.
Do not stop using this medication without first talking to your doctor.
Never reuse a needle or syringe. Dispose of all needles and syringes in an appropriate, puncture-resistant disposal container.
Your doctor may want you to have regularly scheduled blood tests during treatment with interferon beta-1a to determine whether the medication is affecting your liver and to monitor for other side effects.
Flulike symptoms (fever, chills, sweating, muscle aches, tiredness) are likely to occur. They are most common at the start of therapy and may decrease with continued use. Over-the-counter medications for pain and fever may help to alleviate these symptoms. Discuss with your doctor the use of medication to reduce these side effects.
Store unmixed Avonex and prefilled syringes of Rebif in the refrigerator away from moisture and heat. Do not allow the medication to freeze. If refrigeration is not possible, unmixed Avonex is good for 30 days at temperatures up to 25 degrees Celsius (77 degrees Fahrenheit). Rebif may also be kept temporarily at room temperature if refrigeration is not available. If interferon beta-1a is kept temporarily unrefrigerated, such as while traveling, keep it as cool as possible. Do not let it sit in areas that may become very hot such as in a car or in direct sunlight.

What happens if I miss a dose?
If a dose of Avonex is missed, use the missed dose as soon as you remember then resume your normal dosing schedule. Do not however, inject a dose on two consecutive days. Allow at least 48 hours between doses. Do not use a double dose of Avonex.
If a dose of Rebif is missed, use the missed dose as soon as you remember, then skip the following day. Do not inject a dose on two consecutive days, allow at least 48 hours between doses. You can return to the usual dosing schedule the following week. Do not use a double dose of Rebif.

What happens if I overdose?
Seek emergency medical attention.
Symptoms of an interferon beta-1a overdose are not known.

What should I avoid while using interferon beta-1a?
There are no specific restrictions on food, beverages, or activities during treatment with interferon beta-1a. Follow any special instructions given by your doctor.

What are the possible side effects of interferon beta-1a?

If you experience any of the following serious side effects, stop using interferon beta-1a, and seek emergency medical attention or contact your doctor immediately:
  • an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);
  • skin rash, itching, or bumps;
  • depression, anxiety, or suicidal thoughts;
  • seizures;
  • yellowing of the skin or eyes; or
  • unusual bruising or bleeding.
Flulike symptoms (fever, chills, sweating, muscle aches, tiredness) are likely to occur. They are most common at the start of therapy and may decrease with continued use. Over-the-counter medications for pain and fever may help to alleviate these symptoms. Discuss with your doctor the use of medication to reduce these side effects.
Other less serious side effects may be more likely to occur. Continue to use interferon beta-1a and notify your doctor if you experience
  • headache;
  • nausea, vomiting, or loss of appetite;
  • weakness;
  • dizziness or drowsiness; or
  • redness, pain, bruising, or swelling at the injection site.
Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

What other drugs will affect interferon beta-1a?
It is not known if other drugs interact with interferon beta-1a. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including herbal products.

Where can I get more information?
Your pharmacist has additional information about interferon beta-1a written for health professionals that you may read.

What does my medication look like?
Interferon beta-1a is available with a prescription under the brand names Avonex and Rebif. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you.

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

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise.

Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides.

The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.


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