You did steroid instillations? I did those but not with steroids. They used a combo of heparin, lidocaine and saline. Every damn week for a year, I had to go in to the hospital to get my bladder cathed, sometimes twice a week. It got so that I didn’t even notice when they stuck a tube up my urethra, I was so used to it. But it, miraculously, worked. I was SO relieved. That pain is the worst on earth, and I’ve had 3 children! But childbirth, as painful as it is, ENDS. This was that level of pain, burning fiery pain, but neverending. The only thing that helped me was lying in bed with an ice pack directly applied to my privates. They never gave me opiates, because “opioid epidemic”

so I cannot speak to how that may or may not have been effective. Kratom was my only option, so I took it. They did prescribe me a very low dose of Amitriptyline, in fact I still have some of it around. I don’t take it now, because I’m returning to the babymaking gig. It MIGHT have helped, a little? Hard to tell. My urologist also told me to take marshmallow root and aloe vera. I was also taking linaclotide (Linzess) to become more regular (never got to the point where I was pooping every day, unfortunately; once every 3rd day was as good as it got. Now with the purging of all meds and other things for the purposes of purifying my body so as to be a healthy place in which to incubate a tiny human, it’s back to once a week IF IM LUCKY. Sigh. It was nice while it lasted…)
You may have (or had, rather) SIBO, not IBS, if an antibiotic cured it! I suspect I may have that as well; took an antibiotic recently in order to do this test for the fertility clinic and I felt FANTASTIC for the duration of the treatment. Regular, no nausea, etc. but I can’t get my GI doc to take me seriously when I suggested it. Come on, doc, who knows my body better than me?! Seriously tho. It felt like I was on drugs, and I mean the fun kind. They’re not wrong when they say the gut contains the bulk of your serotonin! My mood can be directly traced to how good or bad my gut issues are that day (and btw, my monthly cycle impacts this as well. My gut, I mean, although also my mood; it’s all in roughly the same area, maybe there’s a connection there?

or maybe it’s just difficult to be happy when you’re constantly nauseous, idk)