On a similar note - Fatigue, brain fog ( or cognitive impairment), and restless leg syndrome can be caused by iron deficiency. PV -increased RBC production- and regular phlebotomy make iron deficiency worse…and thus those symptoms.

Have you been diagnosed with pv or polycythemia? I believe that you're on to some reasoning with the lack of oxygen transported to our thinker. The reason I question between the two dx's is because pv's typically have a genetic mutation which can produce mutated blood cells including those that transfer oxygen, that being said there are a slew of symptoms we live with but without studys on them they tend not to be recognized. Sort of an orphan illness. Cheers!

WOW!! now I do not feel so bad! I have brain fog, blurry eyes, and I was not thinking it was related to PV!! glad to know this

Well, I do have some good news: The phlebotomy is helping, my monthly hematocrit is now 49 prior to phlebotomy, and my cognitive issues are easing. Fatigue, itching, and blurry vision in the AM are still problems, but the cognitive relief is real and very much appreciated.

Brain fog is a symptom of PV. I have found that I have the best clarity and cognitive ability early in the day. As my day goes on, I become more fatigued and have difficulty focusing. Thus, I do most of my focused work in the AM. Also, as you will see on another Q/A, a doctor prescribed low does Ritalin for one of our peers and it seemed to help. I asked my doctor about it and she prescribed it for me. I only use the Ritalin when I know I need to have extended focus time like when I was developing a graduate course or grading graduate papers. It seems to help.