The reason they're mixed with protien powder is just to fill up the capsule. The capsules will hold far more than the reccomended dose of dbol, so it needs to be mixed with something else to fill it up. It has nothing to do with settling your stomach. Also, if it's in a capsule, be cautious, as it's most likely from an underground lab, and without knowing which one you could just be taking protien powder.

Another reminder, dbol alone is NOT a good cycle, need some test in there. Good luck.