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A 56-year-old female asked:

One of my fingernails is turning black and they all have ridges. ....what could be causing this?

2 doctor answers3 doctors weighed in
Dr. Mandakini Patel
Pediatrics 42 years experience
Nail issues: The best thing would be to have it checked out as it could be anything from fungal infection to injury or other disease. If you have ridges it could also be fungal infection but it is difficult to say without looking at it. See your doctor. If it developed acutely it could be an injury but you would have known it since it would be painful to have it bleed and have the blood underneath turn dark.
Dr. Stephen Southard
Internal Medicine 16 years experience
Hard to say: Ridges wise, if they are vertical then it's unlikely anything concerning. If they are horizontal - Beau's lines - many things can cause these like stress, nutritional issues, or many different systemic diseases. The color change can be from many things too, as simple as a bruise or concerning things like cancer. Before you get too concerned, please seek input from your doctor.

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Similar questions

A 22-year-old member asked:

What causes these vertical ridges in my fingernails?

3 doctor answers6 doctors weighed in
Dr. Aletha Tippett
Family Medicine 25 years experience
Many reasons: Vertical ridges on nails are basically harmless & can be related to heredity, aging, & nail dryness or injury. The appearance of ridges may be reduced by regular moisturizing of the nail & cuticle & avoidance of harsh soaps that are drying. Nail appearance can reflect overall health and nutrient status so supplementation may help. Consider fish oil, biotin, &/or a multivitamin with minerals.
Dr. Robert Gluck
Hand Surgery 40 years experience
Agreed for the most part though occasionally these can be signs of underlying conditions ie endocarditis, pulmonary issues etc...
Dec 24, 2011
A 35-year-old member asked:

What would cause horizontal ridges on fingernails?

1 doctor answer1 doctor weighed in
Dr. Michael Fisher
Dermatology 33 years experience
Beau's lines: Beau's lines, which are grooves that run horizontally across the nail plate. They usually develop when nail plate growth, which begins in the nail matrix (located under the cuticle), is temporarily disrupted. This can occur with direct injury to the nail matrix; an inflammatory condition such as psoriasis; infection around the nail plate; repetitive picking at the nails or cuticles; or sickness.

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Last updated Sep 28, 2016

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