There is another anti-androgen they can prescribe... I'm drawing a blank right now. I think it starts with an f? I think there is a bit of a risk of liver problems or something which is why they don't prescribe it if spiro works.
Another thing you could try is Vaniqa. My endocrinologist lets me use it anywhere I have unwanted hair even though it is only approved for face. I was a bit nervous about this but my dermatologist also said it was fine...