Brother, don't worry about this. You have to follow some rules to keep your nails clean , don't go in the mud sand, keep sandals on your feet all the time , don't walk barefoot. Every night before going to sleep, clean the corners of the nails and apply 1 drop of the lower drop of the cleanser in this way. If you give it for 3/4 days, you will understand the solution by yourself. The name of the drop is Dermasim . Don't sweat. You make the purchase.