What Causes Dark Neck and How to Treat It

• Dark skin on the neck can either be harmless or a sign of a serious condition
• A dermatologist should make a diagnosis to determine the underlying cause
• Identifying and addressing the underlying condition should be the first priority, followed by topical, oral or skin resurfacing treatments to target the discolored areas

Dark skin on the neck is a common condition that is characterized by a brown or black band of skin or irregular hyperpigmented patches. While a dark neck is usually not a cause for concern, it can also be a symptom of a serious underlying health condition.

Causes of Dark Neck Skin

Patches of brown or black skin on the neck can be caused by several issues and include the following: 

Acanthosis nigricans

Acanthosis nigricans is characterized by patches of hyperpigmentation on the skin. The affected areas become abnormally thick and are velvety to the touch. This skin condition usually develops in skin creases and folds such as the neck, armpits and groin. 

Acanthosis nigricans occurs when skin cells reproduce rapidly, usually as a response to high insulin levels in the bloodstream. It can affect anyone at any age but is more common among people with darker skin tones or those that are obese.

While this skin condition is not a cause for concern, it can be a symptom of a serious underlying condition. Because it’s linked to insulin resistance, it can be a warning sign of diabetes.

Among women, acanthosis nigricans can be a symptom of a hormonal disorder – especially those related to obesity and insulin resistance. One disorder is polycystic ovary syndrome (PCOS), defined by an excess of male sex hormones; another is Cushing’s syndrome, caused by excess cortisol.

Dermatitis neglecta

Dermatitis neglecta is a rare skin condition that is characterized by dead skin cells, sebum and sweat buildup on localized areas of skin due to inadequate cleansing. This buildup appears as a darkening of the skin.

Dermatitis neglecta can occur anywhere on the body, but one common area is the neck. In some cases, the affected area is too sensitive or painful for the affected person to touch (due to another factor, such as surgery), so they avoid cleansing it. This condition can also be an outcome of cognitive impairment. 

Drug-induced skin pigmentation

Drug-induced hyperpigmentation is responsible for 10–20% of all cases of acquired hyperpigmentation. While drug reactions can occur at any age, it is more common among elderly people as they typically take more medications than other age groups. These drugs include:

• Antimalarials
• Nonsteroidal anti-inflammatories (NSAIDs)
• Tetracyclines
• Psychotropics

Sun exposure

Exposure to ultraviolet (UV) light can cause the skin of the neck to become tanned. UV light triggers the production of melanin, the pigment that gives skin its color and protects it from UV damage. The back of the neck is often exposed to sunlight, therefore making it likely to become hyperpigmented. 

Tinea versicolor

Tinea versicolor is a skin condition caused by the fungus Malassezia furfur, a yeast that is naturally present on the skin. An overgrowth of this fungus creates patches of discoloration on the neck, back, chest and arms that can either be hyperpigmented or hypopigmented. 

The risk of tinea versicolor is elevated by hot, humid weather, a weak immune system, pregnancy and medical conditions such as diabetes.

Dark Neck Diagnosis

A dark neck should be examined by a doctor or dermatologist to identify the exact cause of the discoloration. If it is determined to be linked to an underlying condition, the appropriate treatment must be administered. If due to a drug reaction, they may prescribe a different medication.

Your doctor will examine your skin and ask questions about your lifestyle and medical history. They may also request blood work and take a skin biopsy.

Dark Neck Treatments 

The first step in treating a dark neck is to identify if there is an underlying health condition and to then treat that concern. Symptoms should resolve with a correct diagnosis and medication.

If symptoms are not linked to a specific health condition, there are several topical treatments as well as professional therapies that can reduce or eliminate the appearance of a dark neck. 

Antifungal agents

For a dark neck caused by tinea versicolor, an antifungal agent can control the fungus’ growth. 

Zinc pyrithione and ketoconazole topicals can successfully treat this condition; for severe or treatment-resistant cases, oral itraconazole or fluconazole have been found to be more effective. 

Calcipotriol

Calcipotriol is a synthetic form of vitamin D. It’s been shown to effectively treat acanthosis nigricans by inhibiting the growth of keratinocytes, the cells that receive pigment from melanocytes.  

Hygiene

In the case of dermatitis neglecta, darkened skin will not immediately return to its normal color with cleansing. While immediate improvement will be seen, it will take time and a well thought-out skin routine for skin to become healthy. 

Treatment typically involves exfoliation, moisturizing and rubbing alcohol to remove the accumulation of impurities, and help restore skin.

Retinoid creams

Retinoids treat hyperpigmentation on the neck by increasing cell turnover rate and encouraging the growth of new, healthy cells. Unlike some skin lightening agents, retinoids are considered safe for all skin tones. 

Skin resurfacing treatments

Professional treatments targeting hyperpigmentation, regardless of the cause, effectively remedy dark patches on the neck. These treatments use various mechanisms of action to reduce the presence of hyperpigmented cells. Possible options include:

• Chemical peels use gentle acids to remove the top layers of skin
• Laser treatments heat up and destroy hyperpigmented cells
• Microneedling creates microwounds to stimulate new cell growth

Sunscreen

A dark neck caused by sun exposure can be prevented by regularly applying a sunscreen of SPF 30 or higher when outdoors. Wearing a hat or cap, as well as avoiding the sun between 10 a.m. and 4 p.m. will also help protect your skin from damaging rays. 

Home Remedies for Dark Neck

Some home remedies have been proven effective at treating a dark neck that is due to hyperpigmentation. Regular use of these remedies for several weeks or months is usually necessary to see results. 

Aloe vera

Aloe vera contains aloesin, a compound that can address hyperpigmentation. Aloesin inhibits the activity of tyrosinase, the enzyme that stimulates melanin production. With frequent application, this gel can encourage the growth of normally pigmented cells.  

Lemon juice

Lemon juice contains vitamin C, an important antioxidant. Vitamin C reduces the production of melanin-producing melanocytes, allowing skin to gradually lighten. Lemon juice should be diluted with water before being applied to the skin to prevent irritation. 

Rosewater

Although research demonstrating rose water’s efficacy in treating hyperpigmentation is limited,  one clinical trial did determine that rose petal extract reduced tyrosinase activity and  measurably lightened facial skin. Rosewater can be safely applied to the skin multiple times a day. 

Takeaway

Dark skin on the neck is a common occurrence that sometimes indicates an underlying health condition. If the dark skin is diagnosed as acanthosis nigricans, it’s likely caused by diabetes, a hormonal disorder or obesity. 

In other cases, this condition may be a sign of a drug reaction, fungal overgrowth, excessive UV exposure or poor hygiene.

Dark neck skin should be diagnosed by a dermatologist to determine the cause, and any underlying condition should be addressed and managed. Treatments for acanthosis nigricans include topical vitamin D and retinoids, while fungal overgrowth is treated with topical or oral antifungal agents. 

Dark skin caused by poor hygiene can be remediated with exfoliation, moisturizing and rubbing alcohol.

For all types of hyperpigmentation, including acanthosis nigricans, regular use of sunscreen and professional treatments such as chemical peels, laser treatments or microneedling can help resolve symptoms. 

In addition, some home remedies may effectively treat hyperpigmentation by inhibiting melanin production and include aloe vera, lemon juice and rosewater.