Been doing it for years i have reflux also but certain times when brush my teeth i gag for 2 min trying not to throw up why?

More sensitive: The acidity of the acid reflux and just possibly a hyperactive gag reflex may be creating your problems. Sometimes it is good to swish your mouth with very cold water or a strong mouth rinse prior to brushing, especially when brushing your tongue. Trial and error and try not to think about it when doing it.

Sensitive gag reflex: You have a hypersensitive gag reflex. I have the same problem. What works for me is using an electric toothbrush and I purchase a small or child's size attachment head which tends to gag me less. Turn on the electric toothbrush and brush a little and back away. It takes longer to brush this way but you will gag much less