wondering how much breast growth can occur just by taking spriolactone with no other  estrogen's?

Spiro is an anti-androgen, it inhibits the body from using the testosterone produced. I wouldn't think there's too much breast growth from it.

  Inhibition of T will cause breast growth in some men.  This happens when men are over 50 when their natural T decreases and some will grow breasts.  This is called gynecomastia.  I know, I have seen this in the public showers the past 2 years of men my age and older.  Some are larger than mine on hormones!  These are called moobs.  However, these moobs do not develop as well with those with the help of estrogen. 

  Joelene