The thickening of the big toe nail cap bulge should be dealt with according to the specific cause of the disease, usually related to fungal infections, may also be the occurrence of thick nails, according to the actual situation through medication or symptomatic supportive treatment. 1. Fungal infection: common is gray nail, this is the skin fungus invades into the nail plate or under the nail caused by a kind of disease, will lead to big toe nail cover raised thickening, can be under the guidance of the doctor, the use of itraconazole, terbinafine and other antifungal drugs for treatment. 2. Thick nail disease: belongs to a hereditary skin disease, the symptoms manifested as yellowing and thickening of the nails protruding, the thick nail extraction can only temporarily alleviate the symptoms, generally according to the actual situation of symptomatic supportive treatment, such as nail bed shaving surgery and so on. Do not rule out other causes of big toenail cover raised thickening, it is recommended that patients seek medical attention in a timely manner, after a clear diagnosis, under the guidance of the doctor for standardized treatment. Do not treat privately, so as not to induce adverse consequences.