This is one of those things that everyone swears by, yet I had virtually no luck with it when I first tried it. All of the anecdotes and research sounded very promising, but after taking a whole bottle of capsules and seeing little benefit, I dismissed it as another internet myth.
However, I realized later that both trials I made with it occurred before I discovered the gut/bladder connection. When I developed a post-antibiotic UTI recently, I had lots of oregano oil on hand due to trying it topically for the vicious case of staph. I did a quick charcoal cleanse and took OLE and oregano oil only, and drank lemon water.
That UTI was dead in just a few days.