My girl has sensitive nose n often get runny or stuffy nose. Wear socks when sleeping at night. My pediatrician also prescribed Aerius to be taken once at night but my girl is only about 20 mths so not sure if pediatrician will still prescribe same meds or not. No aircon. If you must have aircon, put on eucalyptus essential oil on vaporizer with ac on. If his runny nose not that bad, the socks works wonders.