Brief Answer:
Nail separation (onycholysis)

Detailed Answer:
Hello Ms. XXXX,

If your toe nail otherwise looks normal (no pitting or crumbling), the most common cause of this may be that your toe nail was bumped and sustained trauma. The area where it is separating will look whitish or lighter - that's ok.

You are right to mention fungus as that is another common cause, but not the only one.

Sometimes when separation happens, it happens over time, and so you may not have noticed a trauma that led to the separation.

Sometimes a nail fungal infection doesn't have an abnormal color, but is thickened. If that is the case, you will want to take precautions to keep the nail/skin dry to try to decrease fungal growth. There are antifungal foot powders, lacquers, and other anti fungal medications that can be used if it is a fungal infection. Unfortunately these work with variable success and success is measured in weeks to months. If you go to a health care provider who recommends an oral anti fungal medicine for your toenail, I really advise against this, as an oral antifungal goes through your whole body, including the liver which has to process it, and can be hard on or damaging to the liver in some people. The topical antifungals do not have that risk.

There are other causes for toe nail separation, other than trauma and fungi, but without other symptoms going on elsewhere in your body, they are less likely.

Trim your big toe nail short on a weekly basis until the normal part of the nail has grown. Some say it is best not to use nail polish when they are separated because it can trap moisture under the paint, increasing the chance of developing a fungal growth.

Depending on how much of the toenail is affected, it will either gradually grow out, or in some cases fall off entirely, and a new nail will grow in.

I hope this information helps. Please let me know if I can provide further information.

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