Can I ask why are you switching? It sounds like Tysabri was helping your symptoms from where I am. I have only been on Avonex so far so other treatments are a unknown subject to me. Also washed out fatigue is common symptom for me and many other MS patients. So don't feel alone as its more manageable with pacing your activities and hand some of them to a more able person. Take little breaks regularly and often enough that it doesn't effect your workflow and for long enough that it helps. Breathing exercises help to replenish oxygen in your blood and give your body chance to recover from exercise. If you go all in you will come out worse off. It's a boom and bust effect where you reach your peak and then you are totally out of energy to go on. Pacing with breaks helps level out the energy levels.

Hi I had very bad fatigue and tried sorting it out my self but had no joy . Spoke to my MS nurse and my consultant and they suggested taking modafinil, have been on it for a few months and it has transformed my life. I know everyone is different but I feel fine and don't have any side effects and feel normal and back to my old self. Hopefully you fatigue will sort it self out but if not speak to your MS team they are there to help. I will stop taking the medication in a few weeks and see if my fatigue returns hopefully it won't, take it easy and look after yourself you are the only one that matters.