Short answer: it depends. Some have no dairy. Most have soy, IIRC. I don't think wheat. Even if you buy from the bulk bins, they list the ingredients on the labels on the bins. Always read labels. Then read them again. And then one more time. Not that I've had to learn this the hard way... *sigh*
ETA: a quick google search revealed many ingredient lists. All of them had soy (the least was soy lethicin). Some had dairy. Some had wheat. Yep, just gotta read the ingredients every time, sorry mama.
Nessa, DD1 (5) DD2 (3) & expecting again in late February/early March!