Blood work before starting Propecia?

[itssomuchfun]

I'm probably going to go on Propecia and I'm wondering if I should have any blood work done beforehand. Should I have by Estradiol, Free T, Total T, and DHT levels checked? My dermatologist said he never checks for those and just wanted a PSA run, so I'd have to ask my general practitioner to run these tests since my dermatologist will only do the one.