Have you tried zapping them? It seems to me this might be good as zapping works best for those critters outside the intestines. Maybe you'd need to do this when they are not in your throat or breathing passages so that you don't choke on them if they do die! Still might be worth trying it to get the most annoying ones out of the way...
You can buy a zapper on ebay for $10. I have one that cost around $65 and it has the wrist straps so I use it when I go to bed and take it off after an hr. It does not neg. impact my lifestyle at all.