: Prolonged use can lead to argyria , a permanent condition where silver buildup in body tissues turns the skin, eyes, and organs a bluish-gray color.
: There is no substantial scientific evidence that taking colloidal silver by mouth treats or prevents any disease, including COVID-19, cancer, or HIV. COLLOIDAL SILVER PRODUCTS
: Many commercial products are mislabeled; for example, one study found that 70% of evaluated products contained only ionic silver despite being marketed as "colloidal silver". Colloidal Silver: What You Need To Know - nccih - NIH : Prolonged use can lead to argyria ,