im gonna guess u dont do have bloods telling you how much, if any, u need.
unless u live in a state where they dont have walk-in labs available via online blood testing....
no reason at all to not gets bloods done.
i will second what everyone has said about getting your bloodwork done and also add that you should really try to NOT take it if you don't have to. Even just a small amount of aromasin on a cruise shot down my HDL, i then tapered off and realized I didn't even need it. Cruise dose was 200mg/week.