2nd generation is safer because they don't break the blood brain barrier but 1st generation are still more effective for most people for the very same reason.

That's why I have both Benedryl and prescription Citirizine at home, Citirizine to take on the daily (40mvg 2x daily during allergy season or 8 extra strength reactine a day) to try to deal and Benedryl for when things get bad and I have no other plans.