Melanonychia refers to a nail condition where longitudinal dark bands of the line appear on the nails. Factors like nutritional deficiency, endocrinal disorders, localized tumors, genetic conditions, localized infection, certain medications (cancer and anti-malarial drugs), and injury can cause melanonychia. At times it can lead to pain, splitting, and fissuring of the nail.

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I noticed two brown lines on my thumb which are painful. Why so?

Query: Hello doctor,I noticed two light brown lines on my left thumb that are sometimes painful. I am scared if it is anything serious.Please help.  Read Full »

Dr. Suvash Sahu

Answer: Hello, Welcome to I went through your query and understood your concern. According to your description and the picture shared (the attachment was removed to protect the patient's identity), you have longitudinal melanonychia or linear pigmented lines. The presence of linear pigmented...  Read Full »

Does a dark vertical streak on the nail indicate cancer?

Query: Hello doctor,My daughter has a vertical dark streak along her nail on the middle finger only. It has been there for three months now. There is no known trauma. Could I ask what you suggest we should do? It seems to be darker than before. We went to a dermatologist, and they told us not to worry beca...  Read Full »

Dr. Atishay Bukharia

Answer: Hello, Welcome to At present, she is suffering from longitudinal melanonychia. It is due to the overactivity of the melanocytes, leading to more melanin synthesis. At present, there is no sign of malignancy. Nevertheless, a biopsy is required to confirm the diagnosis. Hope it helps. R...  Read Full »

Why do I have a faint line on my finger?

Query: Hello doctor, I have a faint line on my finger from past ten days. I am attaching a picture of the same. What is it?  Read Full »

Dr. Suvash Sahu

Answer: Hi, Welcome to I have read your concern and examined your picture (attachment removed to protect patient identity).  There is nothing to worry, it is a single nail melanonychia. Nothing actively needs to be done. For further queries consult a dermatologist online --> https://www.icl...  Read Full »

Does nail indentation indicate recurrence of cancer?

Query: Hello doctor, I am a 50-year-old female with stage 1A breast cancer history about seven years ago and treated surgically and with radiation on my right breast. I am on Tamoxifen daily. I was fine since. No other medical conditions. But I have noticed some indentations or slight depressions in my fi...  Read Full »

Dr. Shanza Ikram

Answer: Hi, Welcome to I have gone through the case. In my opinion, you are having melanonychia, but at the same time, you have applied nail color as well. There are a number of causes of such melanonychia in your case. It could be due to 1. Poor diet. 2. Vitamin B12 deficiency. 3...  Read Full »

Why do I have light-colored vertical lines in my fingernails?

Query: Hi doctor, I have recently noticed some light colored vertical lines in my thumb and index finger nails. I have attached the photos for your reference. When I searched on the internet, I found very disturbing things including skin cancer. I have hypothyroidism and chronic depression. I am on Bupron ...  Read Full »

Dr. Atishay Bukharia

Answer: Hi, Welcome to You are having longitudinal melanonychia. It is also one of the signs of hypothyroidism. You might be concerned about melanoma, but melanoma does not present like this. For further information consult a dermatologist online -->  Read Full »

Are dark lines in finger and toenails for a long period a concerning issue?

Query: Hello doctor, I have a dark line in my toenail for a long time, since I was a kid I realize that, but never came into my mind that could be dangerous. The same happened to my fingernail many years after I became an adult. I would like to know if it is something serious and should I care about it?  Read Full »

Dr. Suvash Sahu

Answer: Hi, Welcome you to I have seen your query and examined your given picture. (attachment removed to protect patient identity). It seems you have developed melanonychia. The cause of this are many such as inflammatory nail diseases like lichen planus, racial, nevus in nailbed and rare...  Read Full »

I have got few lines appearing on my nail, which are dark vertical stripes. What could it be?

Query: Hello doctor,I have a few concerns, got a few lines appearing on my nail, which is dark vertical stripes. Especially the one on my right thumb is in the middle, and it has been here for the last two weeks now.  Read Full »

Dr. Atishay Bukharia

Answer: Hello, Welcome to Any symptoms or any other systemic complaints like diabetes or hypertension? And on any medication?  Read Full »

What is the brown vertical streak in my thumbnail?

Query: Hi doctor,I have noticed this very pale light brown vertical streak in my thumbnail about a week ago. I am very worried after reading online about something called longitudinal melanoma. I am 27 years old female.  Read Full »

Dr. Shanza Ikram

Answer: Hi, Welcome to I have gone through your case. Well, longitudinal melanoma is one of the causes of brown streaks. Other causes include multivitamin deficiency including zinc. These are micronutrient and not stored in the body and need a continuous replacement. Other causes include norm...  Read Full »

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