Having severe gray nails cannot be cured with white vinegar. Gray nail is a fungal infection, and the regular treatment is to use antifungal drugs, such as itraconazole and terbinafine, in sufficient quantity and in sufficient courses. If there are contraindications to oral medication, topical medications such as amorolfine application can be used. In severe cases, diseased nails can also be removed by means such as nail extraction. White vinegar is a kind of food, using white vinegar to soak the feet can not kill the fungus, and the fungus of gray nail is mainly inside the nail, white vinegar’s penetration is poor, the content of acetic acid is relatively low, and can not achieve the therapeutic effect, so gray nail is not recommended to use white vinegar treatment. The above medication should be used under the guidance of a doctor, avoid self-medication, so as not to cause adverse consequences.