interferon beta-1a prefilled syringe - injection, Avonex (cont.)
SIDE EFFECTS: Pain, swelling, or redness at the injection site may occur. If any of these effects persist or worsen, notify your doctor or pharmacist promptly.Flu-like symptoms such as headache, fatigue, fever, chills, and muscle aches may occur when you first start this medication. These symptoms usually last about a day after the shot and improve or go away after a few months of continued use. You can minimize these side effects by injecting this medicine at bedtime and using fever reducers/pain relievers such as acetaminophen or ibuprofen before each dose. Consult your doctor or pharmacist for more information.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: mental/mood changes (e.g., depression, thoughts of suicide, new or worsening psychiatric symptoms), hair loss, vision changes, persistent fatigue, numbness/tingling/swelling of the hands/ankles/feet, muscle weakness, trouble breathing, sudden weight gain, gradual change in weight (without a change in diet or exercise), cold or heat intolerance, slow/fast/irregular heartbeat, easy bleeding or bruising, signs of infection (e.g., fever, persistent sore throat), yellowing eyes or skin, persistent nausea/vomiting, stomach/abdominal pain, dark urine.Get medical help right away if any of these rare but very serious side effects occur: chest pain, seizures.A very serious allergic reaction to this drug is unlikely, but get medical help right away if it occurs. Symptoms of a serious allergic reaction may include: 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.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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