Precautions and Warnings With Interferon Beta-1a
You should discuss the precautions and warnings with interferon beta-1a with your healthcare provider before beginning treatment. The medication may cause problems in people with certain medical conditions, so tell your healthcare provider if you have liver disease, depression, or thyroid problems before using interferon beta-1a. Precautions and warnings also apply to people who are allergic to any components of the drug.
You should talk with your healthcare provider prior to taking interferon beta-1a (Avonex®, Rebif®) if you have:
- Liver disease, such as liver failure, cirrhosis, or hepatitis
- Depression or other mood disorders
- A seizure disorder or epilepsy
- Thyroid problems
- Chest pain (angina)
- Congestive heart failure (CHF)
- An irregular heart rhythm (arrhythmia)
- Any allergies, including allergies to food, dyes, or preservatives.
Also, let your healthcare provider know if you are:
- Pregnant or thinking of becoming pregnant
You should also be sure to tell your healthcare provider about all other medicines you are taking, including prescription and non-prescription medicines, vitamins, and herbal supplements.
Warnings and precautions to be aware of prior to taking interferon beta-1a include the following:
- There have been rare cases of heart problems in people taking interferon beta-1a. It is not known if these cases were related to the medication or how exactly it may cause any heart problems. If you have a heart condition (such as congestive heart failure, chest pain, or an arrhythmia), your healthcare provider may need to monitor your heart more closely while you are taking the drug.
- In rare cases, interferon beta-1a can cause liver damage. In some cases, the liver damage was severe enough to require a liver transplantation. You may be at higher risk of this side effect if you already have liver disease or if you are a heavy alcohol drinker.
- Interferon medications (including interferon beta-1a) may increase the risk of depression (see Avonex and Depression or Rebif and Depression). Make sure your healthcare provider knows if you have depression or another mood disorder (such as bipolar disorder or manic depression), or if your depression seems to become worse while you are taking interferon beta-1a.
- In rare cases, interferon beta-1a can cause dangerous allergic reactions. Report any symptoms of an allergic reaction (such as difficulty breathing, wheezing, itching, hives, and swelling) immediately to your healthcare provider.
- Interferon beta-1a can decrease blood counts in some people, leading to low levels of white blood cells (which increases the risk of infection), anemia, low levels of platelets (which increases the risk of bleeding), or other problems. Your healthcare provider should make sure you do not develop these problems by using a simple blood test.
- Interferon beta-1a contains human albumin, which could, theoretically, transmit viruses or other infectious diseases, since it comes from human blood. However, there has never been such a case of infection being passed through albumin.
- Let your healthcare provider know if you have a seizure disorder or thyroid problems, as interferon beta-1a may make these problems worse.
- Interferon beta-1a can interact with a few other medications (see Drug Interactions With Interferon Beta-1a).
- Interferon beta-1a is considered a pregnancy Category C medication. This means that it may not be safe to take during pregnancy. Be sure to talk with your healthcare provider about the risks and benefits of using the drug while pregnant (see Avonex and Pregnancy or Rebif and Pregnancy).
- It is not known whether interferon beta-1a passes through breast milk. Therefore, if you are breastfeeding or plan to start, discuss this with your healthcare provider prior to taking the drug (see Avonex and Breastfeeding and Rebif and Breastfeeding).