Is there anything I can do to help my wife and her allergies? she itches at night and coughs a lot?

Quit making her sleep with the dog. Seriously, have you tried giving the bedroom a really good vacuuming, putting on a barrier sheet to stop anything from the mattress irritating her, swap pillows, or even just put two or three pillow cases on. Anything to try to reduce whatever it is that's affecting her.

try using a betti neti pot. its a very simple process with NO side effects besides breathing clearly haha. medications just cover up the problem, they dont fix it. its like brushing your teeth versus eating a breath mint. covers the bad breath but doesnt kill the problem dont use plastic ones though because the chemicals in the plastic eventually break down and cause more problems. go with ceramic made netis. i have a betti pot and it works wonders. feel better!

If she's tried Claritin and Zyrtec for allergies and they didn't work, then she probably has to talk to a doctor for some prescription medicines like Allegra and an allergy nose spray. She may also be having some mild asthma symptoms triggered by her allergies. That may cause her to cough. A doctor can give her some medicines for that.