I have severe GERD and Anxiety, when the GERD kicks into high gear the anxiety starts up and I have a hard time breathing. I take meds for gerd and the anxiety and those help.
Taking any antispasmatic meds like bentyl or donnatol or hysocamine which are sometimes given to quite the digestive tract do have side affects of breathing trouble.
I dont know if your on those but I was and I thought I was going to die on them.