Is xyzal better then zyrtec my nurse practitioner says it works better bec xyzak was prescription but just now otc. i even took 2 zyrtec once and fail?

No good studies: It's possible there are fewer side effects with Xyzal, but it's unlikely to work better than Zyrtec (both work well). Xyzal is levocetirizine, the l-enantiomer of cetirizine - so in effect, almost the same drug as cetirizine (Zyrtec). No good studies have been done to compare them directly, but it's expected they work very much the same way.