I tried manometry PH test and didn't last more than a couple hours. Same issues as you. Gagging and retching like crazy. Luckily I found a Dr who did Bravo capsules as an alternative. It's basically a tiny capsule that they attach to the inside lining of your esophagus during an EGD which monitors the PH fluctuations and reflux episodes. The capsule monitors for 48 hours and then after a few days it'll natural slough off and you'll pass it like anything else you'd swallow. And no, you don't have to retrieve it lol. You wear a monitor that looks like a pager which records everything. Believe me, I was distraught and hopeless when the manometry didn't work. I had to search Dr's and drive about
2 hours out of town to a Dr that did the Bravo capsule though. It was because of the Bravo that it verified the reflux and prompted them to schedule surgery right away. You have to be off PPI's for at least 2 weeks prior but you can take Carafate up to 2 days before and I think maybe Tums up to a week before if I remember right...so that helps a little but you'd have to double check with your Dr. You log everything u eat and drink, if you burp, if you vomit, etc. with the Bravo just like u would with manometry.
Hope this helps!!