pro advice for your gag reflex try to breathe through your nose and distract yourself by moving other parts of your body for example tap your feet while brushing your teeth also you might try not to touch your brush to your soft palate and back of your tongue and try to buy toothpaste that doesnt contain slssles sodium laureth sulphate which is used for foaming agent the more foam can make you feel more like gag   trust me im studying dentistry and suffering from adhd   edit typo