Thick toenails often signify the presence of the toenail fungus onychomycosis, according to Footsmart. The warm and dark environment in shoes and socks attracts fungus, and when your toenail weakens, that fungus can creep into your toenail beds. In addition to changing the color of the toenail from pale pink to green, yellow or brown, the fungus may cause the nail to thicken or flake. Getting rid of the fungus which causes toenail thickening may take some time, but many find that it is well worth the effort.
Practice proper foot hygiene. According to Footsmart, this means wearing clean socks every day, rotating shoes between wearings and drying toes after showers and workouts.
Apply a topical polish antifungal treatment, such as Penlac (found at most drug stores). Treatment may take up to eight weeks before noticeable differences appear.
If the thickness of the nail persists, continue to Step 3.
Contact a podiatrist. Your podiatrist may prescribe one of several medications, including Sporanox or Nizoral, or other topical medications such as Lamisil or Diflucan, according to Toenail Fungus Treatments. Your doctor might also suggest an oral antifungus medication.
Unfortunately, many oral or strong treatments may cause hepatotoxicity (liver damage), according to Toenail Fungus Treatments, so exercise caution and follow your physician's instructions.