Just FYI and for another point of view, I've been successfully using plain water for two years now titrating four different meds, and it's been working just fine. I don't grind or blend, I just allow the pill to dissolve in the water, and then stir it up well. I keep stirring it as I measure it out so that it stays in suspension.
Since I dose multiple times per day and have to carry the meds around with me in little bottles, water is ideal--no worries about refrigeration.
Personally I would not want to use something besides water because I wouldn't be able to tell by looking at it whether or not it was evenly suspended when I was measuring it out.
As [...] points out, the important thing is that the drug is suspended--it's not going to truly dissolve in anything you can safely drink. But I find that the pills themselves (the binders and fillers) dissolve quite nicely in water if you just let them sit for five or ten minutes.
Personally I think the less you manipulate the pill and the fewer surfaces you expose it to, the more consistent your measurements are going to be from one day to the next, because microscopic amounts of the drug are going to stick to any surface it's exposed to. That's why I avoid the whole grinding and blending business.
So, just for another POV, this is what has been working for me.