You should be fine with flushing

BTW....if you can get ahold of some honey with propolis in it, it will take away the canker sore immediately. Proplis has properties that will totally cure canker sores within hours of taking. Otherwise, your husband may be ok with rinsing his mouth with a baking soda/water preperation (1 teaspoon to a glass of warm water....just swish it around for a few minutes several times a day).

But the canker sore shouldn't have anything to do with flushing. BTW....we have found that it's not necessary to do a parasite cleanse before flushing. It's probably more important to take some herbs or apple cider vinegar to break down the stones than it is to do parasite cleansing.

I did flushes and removed parasites while flushing, but did nothing to kill them at all prior to flushing, though I had done parasite cleanses in the past.