Gray nails generally refers to nail fungus, and need to hang up with the dermatology department. It is usually treated with topical application of amorolfine and oral intake of terbinafine tablets and itraconazole tablets. Nail fungus is caused by fungal infection of the nails, which manifests itself as thickening, color change, flaking, and destruction of the nails, etc. Nails are skin appendages, and skin appendages can be damaged by fungal infection. Nail is a skin appendage, skin appendage lesions in the clinical dermatology category, in the hospital hanging dermatology consultation. Tinea versicolor can be treated in dermatology with topical and oral medications. Topical antifungal treatment can be topical amorphophallus application and other topical antifungal treatment. Topical medications are generally less likely to penetrate the nail, and only early superficial forms may be cured with this method. Generally, only choosing topical treatment can not cure, so topical drugs are mostly used as auxiliary treatment. Nail fungus should be treated with oral antifungal drugs, such as itraconazole capsules or terbinafine tablets. Oral treatment course is longer, need to follow the doctor’s instructions to use drugs, do not stop without authorization. The drugs mentioned above need to be used under the guidance of a doctor, and ringworm of the nails to the dermatology department.