Question: What is your knowledge and experince regarding  the effects
of using numbing injections containing epinephrine on the lower
esophogeal sphincter?

A quick search on the internet found some research indicating it
contracts the sphincter, but not how long this effect lasts.

Question: can the effect be permanent?

Last week I completed a root canal done by an endodontist. It took two
sessions, three months apart. Each time the doctor had difficulty
getting me numb. Last week, following the initial injections, I
experienced heart palpitations, which the doctor explained was most
likely caused by his hitting a blood vessel and that the solution he
used contained epinephrine. He eventually got me numb and finished the
job. That night, I suffered from acid reflux, which I have never had
before and have had it each night since. Some acid gets into my mouth
and burns my throat a bit. Anytime I lie down I almost immediately
experiece the sensation of stomach acid getting into the esophageous.
Discomfort from so called "heart burn" has been very minor, but is
noticeable. I have elevated the head of my bead six inches and that
helps. I have scheduled an appointment with an MD.

Bill

ps: thanks to George and Steve who responed to my post "Time between
visits" following my first session for this root canal.