Thick nails that are not due to a fungal infection will not resolve or improve with antifungal medications.  Therefore, the way to treat the nails is to thin them and this can be done a couple of ways.  First, just as a nail can be filed to reduce its length, nails can be filed to reduce their thickness.  Using an emery board helps to make nails thinner and easier to manage and it also can help decrease discomfort of the nails in closed toed shoes.  Another way to thin the nail and soften it is to use a topical medication which chemically reduces the nail.  Urea is a strong keratolytic – meaning that it breaks down the excessive growth of keratin (which is what nails are made of).  Nail gels when used regularly help to thin nails and can even improve the appearance.