I am not a pharmacologist, so my explanation will be simple....for your benefit and for mine.
Claritin and the other over the counter anti-histamines work by suppressing the formation and effects of histamine which produced the allergic effects that we encounter...e.g runny nose, sneezing, hives etc etc
Any sedative or anti- anxiety effects are secondary.
Hydroxyzine acts in exactly the OPPOSITE way....it 's action is on the brain and main nerves to counteract anxiety. Any anti-histaminic effects are purely secondary.
Both of the above types can be used for their primary uses or their secondary effects.
I hope my explanation is clear.....;-)