from the wiki
"There has never been a reported case of Argyria from the use of a modern "colloidal" silver"
silver compounds and silver ion parts in certain forms can collect in the body. and dont harm you, but make you turn funny colors.
but colliodal silver is the actual metal. it dosnt have that effect on living things. just the antibiotic aspect silver generally has.
thats kinda debatable how effective it is, not a lot of studies have supported it.
but i use it for certain injuries and infections and its always healed me fine. (cuz im anti-antibiotic drugs, not cuz im weird and try weird stuff)