system
Given the following post, respond as if you're commenting on Reddit:
human
What are immunosuppressants, and are the immuno-boosters?

I understand organ recipients need to take immunosuppressants. How do they work? Do different people require different amounts? And is there a reverse immuno-booster?
gpt
There are some drugs that would boost parts of the immune system but only really to be used in specific situations, for example someone with neutropenia post chemotherapy might be offered a drug called filgrastim which can stimulate the bone marrow to produce and release neutrophils.