Hi. Greetings. This appears to be fungal infection of the toe nail. You'll need to see a dermatologist for confirmation of infection and treatment with oral antifungals and application of lacquer. If there's resistance to one particular medicine another medicine may be needed depending on your improvement. If untreated You may end up having fungal infection in other parts of the body, so do keep a check. DO NOT USE OVER THE COUNTER CREAMS LIKE BETNOVATE GM OR PAN DERM OR QUADRIDERM... this will only prolong the infection. Hope this helps.