I have had intractable hiccups for over a year now. A week and a half ago, I was given an epidural steroid injection at L4-L5 for a herniated disc. Within 3 days, my hiccups were much improved (though, sadly, the steroid did nothing for the pain). My first thought was that the steroid had reduced the swelling enough that a nerve was no longer pinched, but research has ground that theory into dust (no nerve that affects the diaphragm/lungs runs along lumbar spine). I know hiccups can be a side effect of epidurals, but mine got better after the injection, not worse.

Does anyone know why this happened, or, failing that, WHY hiccups are a side effect?