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Drugs & Medications

interferon alfa-2a injection

WARNINGS:

This medication can infrequently cause or worsen serious (rarely fatal) medical conditions, including mental/mood conditions (e.g., depression), immune system problems (autoimmune conditions such as lupus or rheumatoid arthritis), circulation problems, or infections. If your medical history includes any of these conditions, tell your doctor promptly. Also, tell your doctor immediately if any serious symptoms or side effects occur (see Side Effects section).

This medication may be combined with ribavirin to treat chronic hepatitis C. Ribavirin may cause harm to an unborn baby or death. Women must avoid pregnancy while they or their male partners are using ribavirin. Ribavirin may cause a blood disorder (hemolytic anemia), which can worsen heart disease. If you are using this medication with ribavirin to treat chronic hepatitis C, also carefully read the drug information for ribavirin.

Who should not take interferon alfa-2a injection?
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Uses

This medication is used to treat various cancers (e.g., leukemia, melanoma, AIDS-related Kaposi's sarcoma). It is also used to treat virus infections (e.g., chronic hepatitis B, chronic hepatitis C, condylomata acuminata). This medication is the same as a protein that your body naturally produces (interferon). In the body, it is thought to work by affecting cell function/growth and the body's natural defenses (immune system) in many ways. Adding more interferon may help your body fight off cancer or virus infections.

How to use interferon alfa-2a injection

Read the Medication Guide available from your pharmacist before you start using this drug and each time you get a refill. Learn all preparation and usage instructions given by the manufacturer. If you have any questions, consult your doctor or pharmacist.

This medication is given by injection into a muscle or under the skin as directed by your doctor. Rotate the injection site each time you inject this medication to prevent soreness. It may also be given by injection into a vein or directly into a lesion, usually by a health care professional.

If you are giving this medication to yourself at home, learn all preparation and usage instructions from your health care professional. Do not shake the medication container (vial or syringe). Doing so may decrease the effectiveness of the drug. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely. Never reuse single-use syringes or needles. It is okay to reuse the multidose pen. It is best used in the evening before bedtime to reduce side effects.

Drink plenty of fluids while using this medication unless otherwise directed by your doctor.

Dosage is based on your medical condition and response to therapy. Do not change the dose or how often you use this medication without your doctor's approval. Use this medication regularly to get the most benefit from it. To help you remember, use it at the same time each evening that you have a scheduled dose.

Different brands of interferon alfa can result in different amounts of medication in the blood. This medication comes in different forms (a powder in a vial, a solution in a vial, and a multidose pen). The way you inject this medication depends on the form you are using. Follow your doctor's directions carefully. Do not switch brands without your doctor's permission.

Side Effects

Injection site reactions (pain/swelling/redness), headache, tiredness, diarrhea, upset stomach, loss of appetite, back pain, dizziness, dry mouth, taste changes, nausea, or vomiting may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.

Flu-like symptoms such as fever, chills, and muscle aches may occur, especially when you first start this medication. These symptoms usually last about 1 day after the injection and improve or go away after a few weeks of continued use. You can reduce these side effects by injecting this medicine at bedtime and using a fever reducer/pain reliever such as acetaminophen before each dose. Consult your doctor or pharmacist for more information.

Tooth and gum problems may sometimes occur during treatment. Having a dry mouth can worsen this side effect. Prevent dry mouth by drinking plenty of water or using a saliva substitute. Brush your teeth well at least twice a day and have regular dental exams. If you experience vomiting during treatment, rinse your mouth afterwards to lessen the chance of tooth and gum problems.

Temporary hair loss may occur. Normal hair growth should return after treatment has ended.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: feeling too hot or cold (more than others around you), fast/irregular heartbeat, increased thirst/urination, menstrual changes (absent/delayed/irregular periods), numbness/tingling of hands/feet, swelling (especially of face/hands/feet), trouble sleeping, trouble walking, vision changes (such as blurred vision, partial loss of vision), easy bleeding/bruising, persistent nausea/vomiting, signs of infection (e.g., fever, persistent sore throat), stomach/abdominal pain, dark urine, black/tarry stools, yellowing eyes/skin.

Get medical help right away if any of these very serious side effects occur: chest pain, seizures, weakness on one side of the body, slurred speech.

This drug may cause you to develop serious mental/mood changes that may get worse during treatment or after your last dose. Tell your doctor right away if you have symptoms such as confusion, depression, suicidal thoughts, unusual irritability, or aggressive behavior. If this occurs, psychiatric therapy and monitoring is recommended during and after treatment with this medication.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

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

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

See also Warning section.

Before using interferon alfa, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients (such as albumin), which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: blood cell disorders (e.g., anemia, neutropenia, thrombocytopenia), blood clots, cancer, diabetes, eye problems, heart disease (e.g., angina, irregular heartbeat), high blood pressure, HIV infection, immune system diseases (e.g., lupus, psoriasis, rheumatoid arthritis), intestinal disease (e.g., colitis), kidney disease, liver disease (e.g., autoimmune hepatitis, decompensated liver disease), lung diseases (e.g., chronic obstructive pulmonary disease-COPD, asthma, pneumonia), mental/mood disorders (e.g., anxiety, depression), high blood triglyceride levels, pancreatitis, seizure disorder, thyroid disease, use/abuse of drugs/alcohol.

This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.

Do not have immunizations/vaccinations without the consent of your doctor, and avoid contact with people who have recently received oral polio vaccine or flu vaccine inhaled through the nose. Wash your hands well to prevent the spread of infections.

To lower your risk of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Children may be more sensitive to the side effects of this drug, especially mental/mood changes (such as severe depression, thoughts/attempts of suicide). Interferon and ribavirin may also slow down a child's rate of growth. Normal weight gain and rate of growth usually return after treatment is completed but the final adult height may be lower than expected. Monitor your child's height and weight periodically during treatment.

Caution is advised when using this drug in the elderly because they may be more sensitive to the effects of the drug, especially dizziness, mental/mood changes, and effects on the heart.

This medication is not recommended for use during pregnancy due to possible harm to an unborn baby and the risk of serious side effects for the pregnant woman. If you become pregnant or think you may be pregnant, tell your doctor immediately. To avoid pregnancy, both males and females using this drug must use reliable form(s) of birth control (e.g., condoms, birth control pills) during treatment with this drug. Talk with your doctor about effective forms of birth control.

It is not known whether this drug passes into breast milk. Consult your doctor before breast-feeding.

Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include: barbiturates (e.g., phenobarbital), colchicine, drugs that may affect your immune system (e.g., cancer chemotherapy, aldesleukin, cyclosporine), hydroxyurea, stavudine, telbivudine, theophyllines (e.g., aminophylline, theophylline), zidovudine.

Overdose

If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: chest pain, persistent nausea/vomiting, stomach/abdominal pain, dark urine.

Notes

Do not share this medication with others.

Laboratory and/or medical tests (such as blood counts, thyroid tests, kidney/liver function, triglyceride levels, eye exams) should be performed before you start treatment, periodically to monitor your progress, or to check for side effects. Depending on your medical history, other tests (such as EKG) may be needed. Consult your doctor for more details.

Do not change brands of interferon without checking with your doctor or pharmacist. Other interferons may not have the same effects on your disease.

Missed Dose

For the best possible benefit, it is important to receive each scheduled dose of this medication as directed. If you miss a dose, contact your doctor or pharmacist immediately to establish a new dosing schedule. Do not double the dose to catch up.

Storage

Store in the refrigerator between 36-46 degrees F (2-8 degrees C) away from light and moisture. Do not freeze. Keep all medications away from children and pets. Consult the product instructions or your pharmacist for more storage details once this medication is mixed.

The multidose pen may be used for up to 4 weeks after the first injection. Do not leave this medication outside of the refrigerator for more than 48 hours. After 4 weeks of use, discard the pen, even if it still contains unused solution.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Information last revised May 2014. Copyright(c) 2014 First Databank, Inc.

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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

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