“Best stone experience ever…” I love that! Like it’s a form of relaxing meditation! But I know what you mean. I could see opiates being a problem for kidney stone excretion. It does slow everything down, notably your bowels (very constipating) so I imagine it could relax all the necessary muscles and urinary excretion too and thus make everything lazy and slow when it came to expelling kidney stones. No matter how ‘meditative’ it is, I can’t imagine anyone would want the process being protracted!
Ironic that Co-codamol was the only drug that eased my gallbladder pain but after I had my gallbladder out I couldn’t use it at all. It caused painful Sphincter of Oddi spasms just like, irony of ironies, gallbladder attacks. Maybe there’s a clue in that. Maybe it was helping to move bile duct stones along, or the opposite, relaxing the ‘peristalsis’ (not sure what that would be called!) that causes the terrible contractions. Either way, I miss it. It was always the only effective drug I could use for migraines - if I caught them early enough.