As long as you follow directions, the answer is no, silver does not kill the good gut flora.
You will see in testimonials that dosage is limited to 1 or 2 tablespoons every 4 hours. If you exceed this and drink 8 ozs at one time, then yes, it will kill the good gut flora. However our flora is located in the large intestine, and limiting dosage to 1 or 2 tablespoons every 4 hours keeps it out of the large intestine. It is absorbed into our bloodstream long before getting into the large intestine.
Also you will see instructions to hold it under the tongue for several minutes before swallowing. This gets a lot of the silver directly into the bloodstream. Also gets the silver ions attached to your metalloproteins in your saliva to carry them through the digestive system and into your cells.
However if you do decide to overdose, then just include probiotics into your program to restore your flora, same as you would do for Antibiotics .