Gray nails medically refers to onychomycosis, fluconazole capsule when used in the treatment of onychomycosis, the use of dosage is related to age, personal constitution and the site of onset of the disease and other factors. 1. Age. When adults use fluconazole capsules to treat onychomycosis, the dosage is 150mg/week. Elderly people need to reduce the dosage appropriately due to the gradual decline of renal function. 2. Individual physique. For the existence of renal impairment of the crowd, need to adjust the fluconazole capsule dosage according to the damage of renal function. 3. Different parts of the disease. Nail fungus is divided into finger nail fungus and toe nail fungus, which is used for finger nail fungus is 150mg/week, continuous use is about 3~6 months. When treating toenail ringworm, the dosage is 150mg/week, and the continuous use is about 6 to 12 months. Adverse effects of fluconazole capsules mainly include headache, nausea, vomiting, abdominal pain, and abnormal liver function, among others. It is contraindicated in people who are allergic to the ingredients of the drug and those who suffer from severe hepatic insufficiency. In order to ensure the safety and effectiveness of the drug, must strictly follow the doctor’s instructions to use drugs, avoid blind self-medication, we recommend that patients timely to the hospital, under the guidance of the doctor standardized treatment.