antihistamines

this is going to sound like a crazy theory, but i have to ask.  I have nasal and eye allergies and chronic idiopathic hives.  Antihistamines work great for my allergiest but not at all for my CIU. I had a major flare the first time I took zyrtec.  Then my hives have gotten better recently but after i stopped taking claritin.  is it possible that when i take the antihistamines, it blocks the histmines from attacking my nose and eyes but then it goes to attack my skin since my hives can't be treated with histamines?  like it's helping the CIU. that sounds bizzare but i can't help but think that...

[National Jewish Health]

Since all of these antihistamines work on th same histamine receptor site, it is hard to understand how your theory might work.

[hyon]

if that's the case...why doesn't antihistamines work for hives?  I can take one dose of claritin and it clears up my nasal and eye allergy is 5min. but it doesn't do anything at all for my hives.