Just thought I'd add my thoughts as I seem to be very sensitive to prolactin.
Mucuna Pruriens (L-Dopa) as mentioned above do work, not well enough for me to have noticed a change.
Tried the B-6 as well, didn't notice anything from that at all sadly disappointing. I tried a few other natural suggestions that all didn't do much except for the wallet.
Your best bet is some Cabergoline or Pramipexole.