I have not had the brain fog but I believe it is part and parcel of the disease and / or meds. I am on pegasys interferon. Google your medication. I read a 32 page report on pegasys yesterday and found all the side effects of which I only have occasional nausea, passes quickly, tiredness some days, some muscle aches here and there. I am on a low dose, only point 25 of a mile. It is working well for me. Platelets came into normal range very quickly. I also have ET, Jacks 2 mutation. I am now in remission after about 16 months.

Sorry but it is. It comes and goes there are days I can take on anything then there are days I just want to chill. I like to play games on my tablet helps with the brain fog. Or play cards with my grandchildren. God bless you

I thought that fatigue was bad , but the Brain fog and lack of concentration is getting worse for me .