I have a prescription for artane (trihexyphenidyl) and i've had it filled at 2 stores... wal mart which carries it in the brand of Danbury and also filled at walgreens where they use qualitest brand. The walgreens brand does not work as well and makes me sick to my stomach quite easily and doesn't do a very good job at relaxing my muscles compared to walmarts brand? Has anyone experienced this with this medication?