Interferon beta-1a (Avonex®) is for injection into a muscle. It may be given by a health-care professional in a hospital or clinic setting. Your health care professional may teach you how to give these injections at home. Make sure you understand how to give the injections and are comfortable with it before you give them yourself. Before preparing an injection always wash your hands well with soap and water. Do not shake the solution before measuring or injecting a dose.