Zyrtec, or Cetirizine HCl should put you about as drowsy as the Claritin does, but it may be more effective. Additionally, your symptoms from the allergies could be treated, rather than the allergies themselves. Is it just a runny nose, sneezing, and perhaps sinus issues? If so, you may want to try psudoephedrine products, including Claritin D, Mucinex D, Non-drowsy sudafed, or things like that. I'm trying to remember other things that I've suggested before...
Oh, you'll have to ask for the things with psuedoephedrine in them, they are, by law, kept behind the counter.
If you're having issues with itching, hydrocortizone cream or benadryl cream could help. Always check the active ingredient, too. There's a lot of allergy products that are just various amounts of benadryl (diphenhydramine HCl, IIRC), and they only say that on the active ingredient label. Describe the symptoms, and maybe I'll remember something that may be a little bit better.