Non formulary vs formulary price

[Gail in Ca]

I have just recently discovered that if my doctor writes 'dispense as written' or 'do not substitute' on my non formulary name brand rx, that I get it for the formulary brand name copay. ( rx's that have no generic)
I was paying $40 for 30 day supply and now can pay $25 for the same rx, if my doc writes those important 3 words!
Thought I would pass this on in case it helps anyone else. BTW, I have blue cross hmo.
Gail