I have used Zyrtec 10mg per day for about a year and a half now. It is the best allergy medicine I have used and my doctor gave me samples of several different ones before we settled on Zyrtec. The only problem with Zyrtec is the price. (I take WelChol for cholesterol too). Thus I get Stanley brand generic cetirizine from Canada where it is over the counter. It costs $30 for 72 tablets.