Hi R.,
Both Sam's and Costco and SO MUCH (unbelievably) cheaper than even Wal-Mart, or any other pharmacy. Call and do price checks at both places, if you don't have a membership card to either. It will be worth the yearly fee of $45 or so just for the RX's!
Also, I'm assuming your daughter is taking Imitrex for migraines. If so, has the doctor mentioned Topamax? It's fairly new and preventative. I haven't had a migraine since I started taking it 1.5 yrs ago! I got it once without my insurance at Costco and it was something like $110 compared to around $300 at CVS, if I remember correctly.
Anyway, RX's are ridiculously high, and it is worth it to "shop around"! I think you will be delighted at the differences in prices you will find at Costco and Sam's Club.... :)
I am believing God's BEST for you!
D.