I can attest to the "something completely different" comment by OP. Monistat does me well, but once in a fit of yeastie desperation, I bought Walgreen's store brand and OMG I could have died.

I looked at the ingredients between the two and while I can't remember what it was exactly, it was not miconazole. I think it started with a T. All I know is, my body definitely did NOT do well with whatever formulation that was.