OK...I'm thinking the difference might be that for using the solution to clean an open wound, you would want to use the product within a short, very specific timeframe.
Since the bladder is not a "sterile" invironment, I think it's OK to use the bottles 4 or 5 days...I've possibly kept one or two open for a week and used it...knock on wood, never had a UTI yet. Mine do not have any short term warning on them.
Very early on, I asked my doctor what I could do in an emergency, if I couldn't get any sterile water...could I use "distilled" water and his reply was something like, it would do the job but it might sting a bit.
But I would only do that in an emergecy...and actually I would probably use "sterile" water sold at the grocery store before using "distilled".
Maybe the medical companies are just putting that info. out there to sell more bottles. We all know how many women were told they needed to have hystorectomies 20 years ago that really didn't "need" them.
And now I notice that 7 out of 10 people I talk with have been told they have sleep apnea and need SPAP.