My Husband Has Severe Gag Reflex. He Currently Has A

My husband has severe gag reflex. He currently has a cold which has made it worse. It's been a problem for about 10 years. We don't know what type of doctor to go to. He's been to our reg. doctor who looks at him like hes crazy. It's so bad that any type of smell will trigger it also having increasing difficulty brushing teeth.