Zyrtec is a second generation antihistamine and while may have 'some' anticholinergic effects, it is a small amount and not a strong one like benadryl or some of the others.

I personally, don't have any anticholinergic or other negative effects from Zyrtec. It may be worth a try for you. If you find it is not helpful or you have unwanted side-effects, then stop it.

If your asthma is allergy triggered, and the Zyrtec controls your allergies, then you may not need a daily asthma med and just use the Ventolin when you have an acute attack. You should consider talking to your doctor about options as well.