In some cases, some Colloidal Silver solutions are believed to affect digestive enzymes.
That said, if you're taking an ionic solution and aiming to get it into the blood stream, then there really is no need to drink it at all as you can simply hold the solution under the tongue for a min. of 5 mins and spit out afterward.
However, if you're targeting the gut, then you may be better served trying a particulate type solution(aka true Colloidal Silver ) as these are said to have better resistance to the acids in your stomach.
Hope this helps
PS. I recall having stomach cramps when I first took CS several years ago also, though it went away after a few days of treatment.