Avonex Overview

Avonex (generic: interferon beta-1a) is a prescription medication that is used to treat multiple sclerosis. Avonex belongs to a group of drugs called immunomodulators, which are thought to help limit the destruction of the protective myelin coating of nerve fibers.

Avonex comes as a liquid for injection into a muscle (IM). It is usually given by a healthcare provider once a week.
Common side effects of Avonex include headache, flu-like symptoms, and fever.