Not what you're looking for? CLICK HERE INSTEAD

The response to the question below was authored by Marc Mitnick DPM

Black Spot Under Nail On Big Toe

by Angel

black spot under toenail

black spot under toenail

Hello everyone,

So around 2 months ago I noticed a black spot under my nail, where previously I had a blood blister, and figured it was probably remnants of said blood blister. Fast forward two months and the spot is still there, however larger (still painless though). When I saw my doctor she did say keep an eye on it as it *could* be melanoma (family history of cancer increases risk). I don't think this is melanoma, but it's been 8 weeks and it's growing.. Before it was more faint, and the size of a pinhead. It is now a bit bigger than that and very dark and noticeable. Could it be a fungus? Could it be a new blood blister that somehow just keeps happening in the exact same spot? I attached a photo for reference. Any advice or opinions welcome!



Hi Angel,

Based on your narrative as to how long you have had the growth and it has not grown forward, plus the fact that you state it has gotten larger, if you presented to my office there would be no question that I would want to take a better look at the growth. I can see that the dark spot is located within a portion of your nail that appears to exhibit nail fungus (yellow discoloration) and this dark spot may just be fungus but there is no way to know by just looking at the toe.

Taking a better look at the growth would mean either cutting back the nail far enough, if I could, to see the
growth or if I could not cut the nail far enough back, I would remove the total nail under local anesthesia. (don't worry, a new nail will grow back and in the process you might be able to clear up the nail fungus as well)

By being able to examine the growth without the nail present I would be able to see if it just dry blood, or fungus, or if it is a growth that needs to be biopsied. Just "watching" it as suggested by your doctor is not a real option at this point.

In the vast majority of cases when I remove a nail to look at a growth similar to yours they end up being benign, but there is the small chance that it could be a melanoma and yes, I have seen them as well.

The fact that the spot is getting larger and NOT growing forward concerns me and therefore should concern you as well.

If indeed this is a melanoma the longer it sits there, the more invasive it will become and thus more serious.

Having it biopsied or at least finding out that the discoloration is just dry blood or fungis is not a big deal. Leaving a melanoma to grow and worsen is a big deal.

Do yourself a favor and it have it examined immediately. At the very least it will give you peace of mind and you will no longer have to worry about it.

Marc Mitnick DPM

If you found this information helpful please let others know by SHARING on social media, thank you.

Click here to post comments

Return to Ask the doctor.


Mayo Clinic

Johns Hopkins Medicine


Arthritis Foundation

University of Rochester Medical Center

Harvard Health

American Academy of Pediatrics

Penn State Medical Center

National Institutes of Health

Columbia University Department of Rehabilitation


Stanford Health Care

Illinois Bone and Joint Institute

Mount Sinai Hospital

Institute for Chronic Pain

University of Florida Health

American Family Physician


University of Maryland Medical Center

privacy policy