What do you do for a patient with an excessive gag reflex, Doctor?

Applying pressure to the front region of the lower jaw may be useful for short procedures such as taking an X-ray, but for long procedures such as root canal treatment there are people who perform an acupuncture-like application in this area using root canal files. I have tried many methods. Sprinkling salt on the tip of the tongue was the most effective.
Another method I use is to administer mandibular anesthesia on the side where I am performing the procedure, even if I am working in the upper jaw. This can reduce the patient's gag reflex