Let the flush be the guide.
There are two imprtant and related factors. How much you have recently eaten and the strength of the flush.
For me, and it could be different for each person, if I haven't eaten for at least 6 hours, then 100mg gives me a good flush.
if I've eaten lke a sandwhich 2 hours before, then 200mg gives a good flush.
I still don't know how much I would need if I had just recently eaten.
A flush ISN'T absolutely required, but is a sure thing. Without flush, but thinking that I may have come close to the flush, I still have benefits, although protection on days 3 to 5 is not as strong.
The best is to try your first attempt first thing in the morning with 100mg. You should get a good flush. Don't take more than 100mg the first time until you see how you react.