I was switched to the premixed when it first came out. We all were.

I had site reactions to it-- huge lumpy swellings. I documented every shot with Biogen. Enough of us complained that they began producing the mix-your-own variety again. The theory is that some of us react to the stablizers that keep it from deteriorating.

At first-- you could only get it by having documentation that you were having problems with the new stuff, and your doc had to order the change.

I don't know how difficult it is to switch to the mix-your-own, but Biogen seems to want folks to use the premix.

Blessings,
PattiLee