Brown spots on the skin may appear suddenly; however, in most cases, these are harmless. They can occur due to a number of causes, including melasma, age spots or liver spots, birthmarks, post-inflammatory hyperpigmentation, moles, seborrheic keratosis, tinea versicolor, and rarely, skin cancer.
Nonetheless, it’s important to have brown spots or patches checked by a doctor to ensure they’re not a symptom of a serious condition, like melanoma.
Brown spot is a general term used to describe any type of brown discoloration on the skin. A brown spot can either be flat or raised.
On the other hand, ‘patch’ is a term often used in dermatology to define any area of discoloration that is flat and larger than 1 cm (if it’s smaller than 1 cm, it’s called a macule). If you touch a brown patch, you won’t feel any raised texture.
Some skin conditions, such as moles and melanomas, can present with both flat and raised brown spots on the skin. However, other skin conditions like melasma and freckles typically only present as flat brown spots or patches on the skin.
Below, you will find 17 causes of brown spots on the skin, along with their pictures and treatment options.
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1. Melasma
Melasma is a chronic skin condition that results in symmetrical brown patches on the face. These patches can sometimes appear gray or bluish-gray.
It can affect various areas of the face, with the upper cheeks and nose being particularly commonly involved. Sun exposure and hormonal changes are strongly associated with this skin condition.
Often referred to as the ‘mask of pregnancy,’ melasma may appear for the first time in some women during pregnancy. Although melasma is harmless, it can be difficult to treat in certain cases.
Treatment
Melasma is a chronic condition that may require ongoing management to improve its appearance. Even after improvement, the brown spots may appear suddenly again due to sun exposure or hormonal changes.
The dark spots caused by melasma can be reduced by using topical treatments that prevent or decrease the formation of melanin pigment. Additionally, increasing cell turnover can help the dark areas fade faster.
The ingredients that may be helpful include hydroquinone, retinoids like tretinoin and retinol, arbutin, kojic acid, azelaic acid, tranexamic acid, and alpha hydroxy acids like glycolic acid and lactic acid.
In some cases, topicals do not give the desired results. In such instances, various procedures or treatments like lasers, intense pulsed light therapy or IPL, chemical peels, and microdermabrasion can be helpful.
Additionally, it’s essential to always use a broad-spectrum sunscreen (at least SPF 30). Sun protection not only helps fade brown patches faster but can also prevent them and protect against skin cancer.
Using sunscreen or other skin care products with iron oxides provides the added benefit of protecting skin from blue light, which can exacerbate hyperpigmentation.
2. Acanthosis nigricans
Acanthosis nigricans can present as light to dark brown patches on the skin. Over time, the skin can become thickened and take on a leathery texture. The most commonly affected areas are the neck, groin, armpits, and under the breasts.
This condition can be caused by a variety of factors, including genetics, obesity, diabetes, hormonal imbalances, and certain medications such as steroids. On rare occasions, it may be a sign of underlying cancer.
Treatment
In many cases, addressing the underlying cause or losing weight can improve the dark patches of acanthosis nigricans.
Topical treatments that decrease melanin pigment or increase cell turnover, like retinoids and alpha hydroxy acids, can also be used. Lasers and chemical peels may be beneficial as well.
3.Tinea versicolor (Pityriasis versicolor)
Brown spots on the skin due to a fungus are usually a result of tinea versicolor (also called pityriasis versicolor). These brown spots typically have a dry or scaly skin surface.
Tinea versicolor is a fungal infection that can alter the pigmentation of the skin, resulting in light or dark patches. These patches can be light brown, dark brown, pale, or white in color.
Sometimes, they become more obvious after a suntan, which might lead one to think that these brown spots appeared suddenly.
The fungus that causes it is Malassezia, which is part of the normal flora of our skin. However, under certain situations like stress or suppression of the immune system, this fungus can overgrow, leading to tinea versicolor.
Other predisposing factors include excessive sweating, humidity, oily skin, and hormonal changes.
Treatment
Tinea versicolor can be treated with over-the-counter antifungal creams, lotions, and shampoos. Miconazole, clotrimazole, ketoconazole, and selenium sulfide are some of the antifungals used to treat it.
After treatment, it may take a while for the skin color to return to normal.
4. Freckles
Freckles are flat skin lesions that contain extra pigment and can be red, tan, yellow, or brown in color. The two types of freckles are:
- Ephelides: These freckles typically appear in childhood. They are small, range from red to brown in color, and do not have well-defined borders. Ephelides are frequently seen on the face, arms, neck, and chest, and usually fade in the winter.
- Solar Lentigines (also known as age spots, sun spots, or liver spots): Age spots appear as flat tan or brown spots on sun-exposed areas, like the face, backs of the hands, arms, legs, or chest in older individuals. Unlike ephelides, they have well-defined borders and do not fade in the winter.
Treatment
Freckles are generally harmless and typically don’t require treatment unless they appear suspicious or for cosmetic reasons. They can be lightened using treatment options like retinoids, lasers, chemical peels, or dermabrasion.
5. Post-inflammatory hyperpigmentation (PIH)
Post-inflammatory hyperpigmentation, often referred to as PIH, is a common cause of brown or dark spots on the skin. PIH refers to the increase in melanin pigment formation in response to inflammation.
This inflammation can be triggered by an injury, trauma, acne breakout, or picking at the skin. It can also be caused by chronic skin conditions such as psoriasis, atopic dermatitis, and seborrheic dermatitis.
Treatment
Brown spots can be faded using ingredients that decrease melanin pigment, such as retinoids, hydroquinone, azelaic acid, and niacinamide.
However, one should be cautious when using topicals with strong actives as they can potentially worsen the underlying skin condition or cause inflammation. It’s best to consult a doctor to discuss the appropriate treatment options.
6. Acne marks
The dark spots left behind by acne also fall under the category of post-inflammatory hyperpigmentation (as mentioned above), but this condition is so prevalent that we will discuss it separately.
Acne is a very common skin problem. It can leave behind marks, which can be either red spots called PIE (post-inflammatory erythema) or brown spots known as PIH (as mentioned above).
Treatment
The treatment of acne marks includes not only fading existing spots but also preventing future acne breakouts. Ingredients such as retinoids, azelaic acid, and salicylic acid can help in lightening these brown spots and also prevent acne.
7. Medication and treatment side effects
Certain oral medications like antibiotics and non-steroidal anti-inflammatory drugs can make our skin more sensitive to sun rays. This can result in the appearance of brown spots on the skin.
Topical medications like hydroquinone or steroids can also lead to hyperpigmentation as a side effect.
Some treatments like laser, chemical peels, microdermabrasion, or IPL (intense pulsed light therapy) can result in pigment alteration due to inflammation. This can result in dark brown patches.
Treatment
In most cases, discontinuing the medication can help improve pigmentation. For resistant cases, ingredients such as hydroquinone and retinoids may be helpful.
8. Shin spots (Diabetic dermatopathy)
Round or oval brown spots or patches on the legs of an individual with diabetes may be due to a condition known as diabetic dermopathy, also referred to as ‘shin spots.’
Diabetic dermopathy is seen in around 50% of people with diabetes. Although it is most common on the legs, it can also appear on other parts of the body, such as the arms and thighs.
These brown spots resemble age spots and are thought to appear due to damage to the blood vessels.
Treatment
Shin spots do not have a specific treatment. These lesions usually start to fade after around 18 months. In addition, it is advised to have blood sugar levels under control.
9. Seborrheic keratosis
Seborrheic keratosis is a benign skin lesion that often appears as a black, tan, or brown spot on the skin. These growths commonly occur on the face, chest, back, or neck, and have a waxy, ‘stuck-on’ appearance.
The exact cause of seborrheic keratosis is unknown, though genetics may play a role.
Treatment
While these growths are harmless, they can become irritated. If removal is necessary, it can be done in a doctor’s office through freezing (cryotherapy), shave excision, curettage, or laser treatments.
10. Urticaria pigmentosa
Urticaria pigmentosa is an uncommon condition marked by the presence of several itchy brown spots on the skin, most commonly on the chest and back. When these areas are rubbed, the mast cells can release histamine resulting in hives. This is called Darier’s sign.
This condition arises from the presence of an excess number of mast cells, which are a type of immune cell, in the skin.
Urticaria pigmentosa predominantly affects children, often subsiding by the time they reach puberty. In rare instances, it may progress to systemic mastocytosis.
Treatment
The treatment is mainly to reduce the symptoms and includes antihistamines and steroids.
11. Moles
Moles are a common cause of brown spots on the skin, and they can be flat or raised, forming a brown bump on the skin. These can be round or oval in shape and occur due to the collection of melanocytes.
Melanocytes are the cells that produce the melanin pigment in our skin, which gives it color. Most of these moles appear in one’s twenties and thirties.
They are usually harmless, however, if there is any change in the shape or color of the mole, one should see a doctor.
Treatment
The majority of moles do not require treatment unless for a cosmetic reason. One should not try to remove a mole at home as it can lead to complications.
Various procedures can be done in a doctor’s office to remove them like freezing, shaving, or burning them.
12. Congenital melanocytic nevus
Congenital melanocytic nevus is a mole that is present at birth or appears shortly after birth. They are usually light to dark brown in color. The size can vary from small to large or giant.
Most of these are harmless. Some, especially those which are large or giant can turn into cancers.
Treatment
Most congenital melanocytic nevi do not require treatment. However, in some cases depending on the size and appearance of the lesion, medical intervention may be needed.
13. Café au lait spots
Café au lait spots are birthmarks that appear as flat, light to dark brown spots on the skin. These spots can darken upon exposure to the sun.
Although often present at birth, they may appear or become more visible with age. These spots usually have irregular edges and can sometimes exhibit varying colors within a single lesion looking like a brown splotch.
While they are harmless, the presence of multiple Café au lait spots (six or more) may be associated with a genetic disorder.
Treatment
Café au lait spots typically do not require treatment. However, if needed for cosmetic reasons, laser treatment may be considered, although responses to this treatment can vary.
14. Actinic keratosis
Actinic keratosis is a precancerous lesion of squamous cells. It occurs due to DNA damage to the squamous (usually due to exposure to sun or certain chemicals).
It can present as a rough scaly spot which can be brown, tan, skin-colored, white, pink, or red in color. If left untreated, it can turn into squamous cell carcinoma in some individuals.
Treatment
Actinic keratosis is usually treated by topical medications, cryotherapy, or local excision.
15. Melanoma
Melanoma is a skin cancer that involves melanocytes, the same cells which make melanin pigment in our skin. This cancer can present as an asymmetric brown spot with irregular edges. The size is usually more than 6 mm.
Melanoma can occur in areas exposed to the sun as well as in hidden areas like between the fingers or under the nails.
Treatment
Melanoma treatment depends on the size of the lesion and its spread to various other organs. The treatment may include surgical excision, lymph node removal, radiotherapy, or chemotherapy.
16. Basal cell carcinoma
Basal cell carcinoma, the most common type of skin cancer, may present as a waxy red, pink, tan, white, skin-colored, or brown spot or patch, or as a non-healing ulcer.
Basal cell carcinoma occurs as a result of DNA damage, primarily from UV rays. Lesions are typically observed on sun-exposed areas such as the face, neck, scalp, ears, and trunk.
Treatment
The choice of treatment depends on various factors, including the size, type, and location of the carcinoma. Mohs surgery or surgical excision are common treatment methods. Other options include laser treatment, cryotherapy (freezing), and curettage.
17. Squamous cell carcinoma
Squamous cell carcinoma is the second most common type of skin cancer, following basal cell carcinoma. It may present as a scaly patch, an ulcer, a firm nodule, or rough, bumpy growth.
The cancer spots can vary in color, ranging from red and purple to various shades of brown. Though it commonly appears in sun-exposed areas, it can develop anywhere on the body.
Squamous cell carcinoma results from DNA damage in the squamous cells. Risk factors include fair skin, sun exposure, use of tanning beds, a compromised immune system, or a history of previous squamous cell carcinoma.
Treatment
Treatment options for squamous cell carcinoma may include curettage, cryotherapy, laser treatment, Mohs surgery, surgical excision, or radiation therapy.
Diagnosis
The diagnosis of the underlying cause of brown spots or patches on the skin is typically made through a physical examination of the skin and a comprehensive review of the patient’s medical history by a healthcare provider.
The healthcare provider may gather detailed information about the patient’s family history, any pre-existing skin conditions, history of trauma or injury, and any medications the patient may be taking.
In certain cases, additional tests may be performed to confirm the diagnosis.
These may include:
- Blood test to rule out any hormonal disorders.
- Skin scrapings to look for fungal elements.
- Wood lamp examination for pigmented or infectious lesions.
- Skin biopsy to see the tissue under the microscope.
Prevention
- Be gentle with your skin and avoid rubbing aggressively.
- Consider using fragrance-free and essential oil-free skincare products if your skin is sensitive.
- Avoid excessive exposure to the sun.
- Always use sunscreen and sun-protective clothing.
- Follow guidelines given by your doctor after procedures like chemical peels and lasers.
- Avoid contact with known allergens and irritants.
- Make sure to use your treatment if you are dealing with any chronic inflammatory skin condition like psoriasis, atopic dermatitis, etc.
Key points
Brown spots on the skin can occur due to birthmarks, melasma, acne marks, age spots or liver spots, moles, seborrheic keratosis, tinea versicolor, and rarely, skin cancer.
The majority of brown patches or spots on the skin are harmless. However, sometimes a brown spot on the skin can indicate serious skin conditions like melanoma, a type of skin cancer.
It is important to see a doctor to get a proper diagnosis. Timely treatment of melanoma and other skin cancers is crucial to prevent the spread of cancer cells.
References
- Bandyopadhyay D. Topical treatment of melasma. Indian J Dermatol. 2009;54(4):303-9. doi: 10.4103/0019-5154.57602. PMID: 20101327; PMCID: PMC2807702.
- Desai SR. Hyperpigmentation therapy: a review. J Clin Aesthet Dermatol. 2014 Aug;7(8):13-7. PMID: 25161755; PMCID: PMC4142815.
- Macri A, Cook C. Urticaria Pigmentosa. [Updated 2021 Aug 11]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan.
- Hassan S, Zhou X. Drug Induced Pigmentation. [Updated 2022 Jul 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan.
Disclaimer: This blog post is for information purposes only and does not replace medical advice.