if you have yet to master the quiet sneeze... you stash tissues like a squirrel stashes nuts... well muddlers, muddle no more. try zyrtec®. it gives you powerful allergy relief. and zyrtec® is different than claritin® because zyrtec® starts working at hour one on the first day you take it. claritin® doesn't start working until hour three. zyrtec®. love the air.