I have experienced everything you are talking about! I started getting acid reflux about a year and a half ago. It started out of the blue but with reflux I would get really fast heart rates and shortness of breath. I was treating it with Prilosec. After being on it a few weeks I had a freaky episode where I couldn't breathe and my heart rate was hitting in the 160's. I ended up in the ER and they did an EKG and it was normal. The doctors all thought I was just having a panic attack. I didn't think so.
I went to my GP and they put me on daily Prilosec and my symptoms got worse. Since the acid reflux wasn't getting better I was then switched to Protonix. Once again all the symptoms were even more frequent and intense. Jittery feeling, numbness in my arms and legs, tingling in my face, mouth, a lot of different things but the worst was always feeling like I was choking and couldn't breathe. After a few weeks on the medication I started with feeling depressed and the anxiety got worse. Like you mentioned, not feeling suicidal but feeling like you are going to die, kinda visualize some random accident happening and you die, or you are sick, feelings that you can almost see yourself dying, if that makes sense. Almost a feeling of not being connected to anything. It freaked me out. I'm not at all like that. Scary. Nothing was getting better, so I was sent for an endoscopy.
I had the endoscopy and nothing crazy was found. I did have acid reflux. The gastroenterologist suggested I take Prontix twice a day. Against my better judgement I did. Big mistake. All my symptoms intensified. The depression, the anxiety, the choking, the jittery muscles, acid reflux, back pain, headaches, weird sensations of hot spots in my muscles, numbness, insomnia, and I then I started getting really bad abdominal pain.
I went to a lot of doctor appointments, ended up in urgent care 4 or 5 times with crazy out of control heart rates. They then thought I had anxiety and giving myself reflux from anxiety attacks. They tried giving me ativan, it didn't work. They did several more EKG's and IV's and even allergy medications, nothing worked.
I was pretty convinced it was the meds that were making me feel crazy!! They then thought maybe it was my gallbladder, so I had an abdominal ultra sound- nothing was wrong. So I went to a new gastroenterologist and he said from my Endoscopy he could tell I did have acid reflux and that I might me intolerant to the medications. That it IS possible! So many doctors told me no. He said all these acid reflux meds are different but in the same class and have common elements that some people are intolerant to. Prilosec, Protonix, Prevacid are all in the same class. He wanted me to test out Prevacid to see if that one had the same effect as the others, it does. I'm now scheduled to take a test to see if I am intolerant to all of these. These three medicines are all "zole" medications- the non name brand names of each of these all end in zole.
I don't know the results of that test yet, but he said those who are intolerant have to be treated in an "old school" medicine way that requires him to try medications that were used before this class of medications was thought to work best. It was explained to me that some other over the counters like Zantac are a little better because they don't stay in your system. Even if you have problems with them they go through you in hours so they don't have long enough time to cause all the other crazy side effects. So they are a quick fix to bad reflux symptoms but hopefully get out of your system before causing too many side effects.
When I tried a week off of Protonix, Prevacid, Prilosec I felt so much better as far as side effects. The reflux had to be managed with Zantac but the crazy feelings started to go away. Maybe try talking to a gastroentrologist about giving that a try as well.
Good luck with your EDG!