Vinegar garlic is not a treatment for gray nails. Although vinegar-soaked garlic has some fungal inhibiting effect, it has a very limited effect on fungal infections of gray nails. This is because this kind of thing does not work at all to kill the fungus especially the fungus deep in the nail plate, at most it only inhibits the growth and reproduction of the fungus, so this kind of treatment is not reliable. The most reliable way to treat gray nails is to take oral antifungal medications, such as itraconazole, or terbinafine. Topical topical medications are usually used, such as amorolfine cream, or amorolfine rub, etc.