Eight years for me, no problems ever, and can't walk without it.
Here's the best group for Information and testimonies for Ampyra.
https://www.facebook.com/groups/131179136896972...
Been taking for a few years, if I forget I have a really hard time moving the next day. No side effects.
I have Spasticity, big time, on my right side - shoulder, arm and leg. It is also on my left side however, not as bad. I took Ampyra for one year. I experienced no side effects. But I did not experienced any improvement in my mobility so I discontinue. I will tell you that it would be worth trying.
No I have been on Avonex for 22 years, since day one of being diagnosed. 👍