Are there some people that just cannot be cured from severe anemia? I have go through two blocks of 10 units of IV iron (Venifer) over the last 6 months. My numbers come up for a bit but within a few weeks, I m right back where I started. Plus, the effects of the Venifer only last a few hours for me. Then, I m exhausted and just want to sleep again. Please advise. Thank you.