Hi Silas. Welcome! There are many methods of getting the chlorine dioxide into the blood stream. You've mentioned two. it can be app[lied to the skin as a spray, added to a bath or even as a gas in a plastic bag. Whichever works for you as it gets into the bloodstream with all those methods.
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As I recall , asthma is caused by ascaris worms in the lungs. Until you can get rid of the source of the worms you might as well think of taking maintenance forever, for if you stop, you'll be reinfected.
After reading the book, feel free to come back with any other questions that arise.