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Interferon beta-1a and Albumin human intramusc.

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.


(in-ter-FEER-on BAY-tuh)



This medication is used in the treatment of multiple sclerosis (MS).



This drug may also be used for the treatment of certain cancers, immune system disorders or viral infections.

How To Use

This medication is administered by injection into a muscle generally once a week. Do not change the dose or use this more often than directed. This medication may be self-administered. Make sure you understand how to properly prepare the medication, give the injection and properly dispose of used syringes and needles. Read the Medication Guide provided by your pharmacist. If you have any questions regarding the information, ask your doctor or pharmacist.

Side Effects

Headache, nausea, fever, flu-like symptoms, muscle aches, chills and irritation at the injection site may occur. If these persist or worsen, notify your doctor promptly. Flu-like symptoms can be treated with fever reducers and pain relievers such as acetaminophen or ibuprofen. Consult your doctor or pharmacist. Tell your doctor immediately if any of the following serious side effects occur: chest pain, swelling of the ankles/feet, sudden weight gain, sleep problems. Tell your doctor immediately if any of the following unlikely but serious side effects occur: mental/mood changes or depression (including thoughts of suicide), seizures, signs of infection (e.g., persistent sore throat), easy bruising/bleeding, dark urine, yellowing eyes or skin, extreme fatigue/weakness, cold or heat intolerance, gradual change in weight (without a change in diet or exercise), fainting, rapid or irregular heartbeat. An allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of an allergic reaction include: rash, itching, swelling, dizziness, trouble breathing. If you notice other effects not listed above, contact your doctor or pharmacist.


Before using this drug, tell your doctor your medical history, including: allergies (especially drug allergies), heart disease, seizure disorder, psychiatric disorders (e.g., depression), liver disease, thyroid disorders (hypo or hyperthyroidism). This drug may make you more sensitive to the sun. Avoid prolonged sun exposure. Wear protective clothing and use a sunscreen. Limit alcohol, as it may aggravate the side effects of this medication. If you become dizzy while using this drug, especially when arising from a seated or lying position, stand up slowly. This medication is not recommended for use during pregnancy due to the risk of serious side effects for a pregnant woman. Consult your doctor for more details. It is not known whether this drug is excreted into breast milk. Because of the potential risk to the infant, breast-feeding while using this drug is not recommended. Consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all nonprescription and prescription medication you may use. Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately.


Do not share this medication with others. This drug is not a cure for MS but has been shown to slow the advancement of the disease. Laboratory tests will be done periodically while you are using this drug to monitor for side effects.

Missed Dose

If you miss a dose, contact your health care provider who will establish a new dose schedule. Do not double the dose to catch up.


Store in the refrigerator between 36 and 46 degrees F (2-8 degrees C) away from light and moisture. If your medication comes in a vial, use the solution as soon as possible after preparing it. Discard any unused solution in the vial after six hours. If using the prefilled syringes, remove from the refrigerator and allow the medication to warm to room temperature (about 30 minutes) before injecting. Use the medication in the syringe within 12 hours after removing it from the refrigerator.