Well, crap.

Cranberry juice no benefit for kidney stones?

In both, the cranberry juice increased urine levels of calcium and oxalate. Levels of brushite did decrease, but this substance causes a different type of kidney stones (known as brushite stones), which are comparatively rare.

Not that I've been hitting the Ocean Spray in hopes of avoiding another kidney stone. It was just kind of nice to have the idea that there was something that could help.