Avonex (interferon beta 1a injection) (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:


  • Single-dose prefilled syringe: 30 mcg/0.5 mL.
  • Powder for injection (single use vial): 30 mcg.
  • Autoinjector: 30 mcg/0.5 ml


  • Combining interferon beta-1a with zidovudine (Retrovir) or hydroxyurea (Hydrea) may increase the risk of bone marrow suppression with reduced blood cell counts.


  • Use of interferon beta-1a has not been adequately evaluated in pregnant women. Due to the lack of conclusive safety data, interferon beta-1a should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus.
  • It is not known if interferon beta-1a is excreted in breast milk. As many drugs enter breast milk and can potentially cause harm to the nursing infant, interferon beta-1a should be used cautiously in nursing mothers


  • Preferably interferon beta-1a should be stored refrigerated between 2 C to 8 C (36 F to 46 F).
  • If needed, interferon beta-1a powder can be stored at 25 C (77 F) for up to 30 days if a refrigerator is not available. It must be used within 6 hours if refrigerated at 2 C to 8 C (36 F to 46 F) once the powder is diluted with solution
  • The autoinjector and prefilled syringe may be stored at 25 C (77 F) or lower temperatures for 7 days if a refrigerator is not available. Once the product is removed from the refrigerator, it must not be stored above 25 C (77 F).
Medically Reviewed by a Doctor on 6/8/2016

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