{"id":6048,"date":"2025-05-23T17:52:51","date_gmt":"2025-05-23T15:52:51","guid":{"rendered":"https:\/\/clinicasanroman.com\/brown-toenail-causes-diagnosis-and-podiatric-treatment\/"},"modified":"2025-06-03T15:18:32","modified_gmt":"2025-06-03T13:18:32","slug":"brown-toenail-causes-diagnosis-and-podiatric-treatment","status":"publish","type":"post","link":"https:\/\/clinicasanroman.com\/en\/brown-toenail-causes-diagnosis-and-podiatric-treatment\/","title":{"rendered":"Brown toenail: causes, diagnosis and podiatric treatment"},"content":{"rendered":"\n
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Brown nails<\/strong> is a clinical condition that is of concern to many patients, especially when it appears suddenly or affects only one nail. This unusual coloration may manifest as a longitudinal band, an irregular spot or a generalized change in the color of the nail plate. Although in many cases the cause is benign, in others it may indicate serious conditions that require specialized medical attention. <\/p>\n\n\n\n

At Cl\u00ednica San Rom\u00e1n we approach this type of problem with a comprehensive approach, based on years of experience in advanced clinical podiatry. In this article we will detail the main causes, the diagnostic approach and the most appropriate treatments depending on the origin of the brown nail, as well as recommendations for prevention and control. <\/p>\n\n\n\n

What exactly is a brown nail?<\/h2>\n\n\n\n

The term \u201cbrown nail\u201d refers to an alteration in the usual coloration of the nail, which changes from its usual pink and translucent tone to a brown, black or dark brown pigmentation. This change can affect both fingernails and toenails, although in podiatry it is more frequently observed in the toes, due to increased exposure to pressure, friction and trauma. <\/p>\n\n\n\n

This coloration can take different forms: a vertical stripe known as striated melanonychia<\/strong>, a circular or oval spot, or a diffuse hue covering the entire nail. Each of these forms may be associated with different causes, so it is essential to make a proper clinical assessment. <\/p>\n\n\n\n

Main causes of brown nails<\/h2>\n\n\n\n

There are multiple causes for the appearance of a brown nail, from traumatic and fungal reasons to systemic diseases or even skin cancer. Here are the most frequent ones: <\/p>\n\n\n\n

1. Subungual trauma and hematomas<\/h3>\n\n\n\n

Repetitive minor trauma (e.g. running or wearing tight shoes) can cause capillaries under the nail to rupture. This results in a subungual hematoma that manifests as a brown or blackish stain. Although usually benign, if the spot does not move with the growth of the nail or appears with no apparent bump, it should be investigated further. <\/p>\n\n\n\n

2. Fungal infections (onychomycosis)<\/h3>\n\n\n\n

Onychomycosis<\/strong> can cause changes in nail coloration, with yellow, brown or greenish tones, as well as thickening, brittleness and deformity. Diagnosis is made by mycological culture and direct examination, and treatment may be prolonged, with topical or oral drugs. <\/p>\n\n\n\n

Melanonychia<\/h3>\n\n\n\n

Melanonychia is the presence of brown or black pigment due to increased melanin in the nail matrix. It can be physiological (in dark-skinned or elderly people) or pathological. In the latter case, it may be due to a nevus or, in severe cases, to a subungual melanoma, a type of cancer that requires early detection. <\/p>\n\n\n\n

4. Drug-induced pigmentation<\/h3>\n\n\n\n

Some drugs such as those used in chemotherapy, antimalarials or antibiotics (minocycline, doxycycline) can induce nail pigmentation as a side effect. This color change usually affects several nails symmetrically and may be reversible after discontinuation of treatment. <\/p>\n\n\n\n

5. Systemic diseases<\/h3>\n\n\n\n

Some chronic pathologies such as Addison’s disease, chronic renal insufficiency, vitamin B12 deficiency or endocrine disorders can be reflected in the nails, generating color alterations. In these cases, brown nails are only one of several clinical signs that occur together. <\/p>\n\n\n\n

6. Exposure to chemicals<\/h3>\n\n\n\n

Handling chemical substances without protection, such as dyes, cosmetics or industrial products, can pigment the nail surface. This pigmentation is usually superficial and reversible, but should be checked if it persists longer than usual. <\/p>\n\n\n\n

\"brown<\/figure><\/div>\n\n\n\n

Clinical and podiatric diagnosis of brown nails<\/h2>\n\n\n\n

Proper diagnosis of a brown nail<\/strong> is essential to rule out serious pathologies and guide treatment. At Cl\u00ednica San Rom\u00e1n we perform a complete evaluation protocol that begins with a detailed anamnesis: the patient is questioned about the evolution of the color, history of trauma, use of drugs, systemic symptoms and family history. <\/p>\n\n\n\n

Subsequently, a physical inspection of the affected nails is performed. Signs such as asymmetry, irregular edges, uneven coloration or bleeding are indicative of lesions that should be studied further. <\/p>\n\n\n\n

Diagnostic tools<\/h3>\n\n\n\n