Beaus lines are horizontal indentations or ridges across fingernails or toenails, sometimes with a yellowish tint.
They indicate an interruption in nail growth, often due to illness, injury, or other underlying factors.
The width of the line may provide clues about the cause.
Dmytro Skrypnykov / Getty Images
Dmytro Skrypnykov / Getty Images
What Are Beau’s Lines?
Beaus lines arehorizontal ridgesor dents that form across your nails when nail growth is temporarily disrupted.
Beau’s lines dont develop randomlythey are a sign that an underlying issue is affecting your body.
Reproduced with permission from © DermNetdermnetnz.org2023.
Reproduced with permission from DermNetdermnetnz.org2023.
Generally speaking, they can be described as indentations or grooves that run side to side across the nail.
While they can appear on just one nail, most people have them on multiple nails.
bbbrrn / Getty Images
Causes
The exact cause of Beau’s lines isn’t fully understood.
This temporarily slows nail production, leading to the formation of grooves or ridges.
When Should You Worry About Beau’s Lines?
Beaus lines can be concerning, especially considering how many possible causes there are for their appearance.
Its important not to jump to the worst-case scenario.
The most common cause is tied to medication use, specifically in people already undergoing chemotherapy.
They will also ask you about any recent illnesses, injuries, or medications.
The grooves position helps determine whether the cause is short-term (acute) or long-term (chronic).
Chemotherapy-related Beaus lines often align withtreatment cycles, with each groove marking when a round of treatment occurred.
By analyzing these details, providers can distinguish Beaus lines from other nail conditions and identify the cause.
Treatment
Treatment for Beaus lines focuses on addressing the underlying cause rather than the nail ridges themselves.
For example, adjusting chemotherapy regimens,controlling diabetes, or treating infections may support healthier nail growth.
If trauma caused the lines, avoiding further injury and maintaining good nail care can help.
Since fingernails and toenails grow slowly, it may take several months for the affected nails to fully recover.
Summary
Beau’s lines are horizontal dents in the nails.
They can be due to diseases, injuries, infections, or even nutrient deficiencies.
One of the most common reasons for Beau’s lines is chemotherapy.
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