Discoloration of your toenail is very common and can be caused by more than a common fungal infection. The color and overall texture can help your podiatrist discover the underlying cause of the nail color. Some diseases that may cause nail discoloration include medications, chemotherapy, systemic diseases and skin cancers. In some cases, discoloration can occur if you naturally have dark or pigmented skin. If concerned about the discoloration, possible biopsy or removal of the nail for further inspection should be considered. If you have other questions about the color of your nail you should consult your podiatrist.