Nail discoloration can be the result of a seemingly endless list of causes: fungal infection, the body’s response to medications, a change in hormones, even pregnancy, just to name a few. In cases like this, the discoloration appears over the whole nail and across multiple fingers. Techs also regularly see isolated discoloration, which could be round, oval, or linear. These are the occurrences more likely to be a health concern. Before you dismiss that dark spot as harmless and move to beautify the nail with an enhancement, take a few minutes to talk with your client to learn the back story. That conversation may go something like this:

You: I haven’t noticed this dark line in your nail before. How long has it been there?

Client: That’s funny. I just noticed that this week too. Does it concern you?

You: Not necessarily, but it’s definitely something to watch. It’s not on any other fingers, which makes it more suspicious. You may have hit, pinched, or slammed your nail and this is just evidence of that trauma. In that case, it would be your standard “subungual hematoma,” or bruise. We’ll monitor it to see if it grows out.

It may also be something as benign as an increase in melanin pigment on this area of the skin. It’s almost like a freckle forming. A melanin increase doesn’t necessary indicate a problem either; it happens every time our skin darkens from a tan.

However, if it doesn’t grow out, and instead it changes shades or continues to widen, you will want to get it checked as soon as possible. A dermatologist will be able to perform a biopsy to rule out melanoma.

Client: What? Could that be skin cancer?

You: Well, the only way to know for sure is by making an appointment with a dermatologist, and it’s always best to be safe. Caught early, melanoma is highly treatable, but when we wait, treatment is less successful.

I don’t want to scare you. These dark bands are common and are usually harmless. They appear just as other spots appear on our body as we age. They are quite common in people who have naturally darker skin. So don’t get nervous. But do monitor it. First, watch for changes in color. If different shades of tan, black, and brown widen on your nail, or if it becomes fuzzy or blurred, see a doctor. Also, watch the skin on your cuticle. If that pigmentation darkens, schedule an appointment immediately.

Client: What do we do right now?

You: Let’s keep the enhancement off this nail and polish with a light color so you’ll be able to see any changes. I’ll also make a few notes in your file here so we can check it at your next appointment. If it grows out, or we see multiple bands across more than one nail, that’s a good sign. But if this one expands or changes color, make an appointment.

Client: Wow. OK. I’m glad you said something.


Refer to a doctor if you see any of these three symptoms:

> A single dark line on a single finger

> A dark line on the index finger, thumb, or big toe (where melanoma is more commonly found)

> Brown pigmentation on the cuticle


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