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[Over the Counter](https://www.health.com/over-the-counter-products-8651366) - [Skincare](https://www.health.com/skincare-products-6951522) - [View All](https://www.health.com/what-to-buy-6951517) [About Us](https://www.health.com/about-us-8415145) - [Editorial Process](https://www.health.com/health-com-s-editorial-process-5224046) - [Medical Expert Board](https://www.health.com/health-com-s-medical-expert-board-5224047) - [Testing and Vetting Products](https://www.health.com/how-health-com-test-products-5224057) # 10 Causes of Underarm or Armpit Rashes You Need To Know By [Karen Pallarito](https://www.health.com/author/karen-pallarito) ![KP Headshot IMG\_1661]() :max_bytes\(150000\):strip_icc\(\)/KP-Headshot-IMG_1661-0d48c6ea46f14ab19a91e7b121b49f59.jpg) [Karen Pallarito](https://www.health.com/author/karen-pallarito) Karen is a senior editor at Health, where she produces health condition “explainers” backed by current science. [health's editorial guidelines](https://www.health.com/health-com-s-editorial-process-5224046) Updated on February 1, 2026 Medically reviewed by [William Truswell, MD](https://www.health.com/author/william-truswell-md) ![Willliam Truswell, MD]() :max_bytes\(150000\):strip_icc\(\)/WilliamTruswellMD-65d333ba98a14c2db5b0af4e8e139534.jpeg) Medically reviewed by [William Truswell, MD](https://www.health.com/author/william-truswell-md) William Truswell, MD, FACS, operates his own cosmetic and reconstructive facial surgery practice. Dr. Truswell was the first in his area in Western Massachusetts to have an accredited private office surgical suite. [learn more](https://www.health.com/health-com-s-medical-expert-board-5224047) - Many over-the-counter creams work best for some armpit rashes. - Contact dermatitis on your armpits is caused by exposure to skin irritants or allergens. - Shaving can cause folliculitis, which looks like a zit-like rash. Armpit rashes can develop from infections, allergies, or irritation. Symptoms range from mild itching to severe inflammation. ![Person examining their itchy armpit.]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-1750149618-c2404ad126df4f098cc3b6b559120edc.jpg) [buraratn](https://www.gettyimages.com/search/photographer?photographer=buraratn) / Getty Images ## 1\. Contact Dermatitis This rash is caused by exposure to an irritant or an allergen. [Contact dermatitis](https://www.health.com/contact-dermatitis-7377965) has two main types, each causing an itchy, burning, or painful rash: - **Allergic contact dermatitis** occurs when the skin comes in contact with a substance that provokes an immune response. Your rash could be an allergic reaction to fragrances, preservatives in soap and skin products, or [poison ivy](https://www.health.com/condition/skin-conditions/home-remedies-for-poison-ivy) (presuming you recently had a brush with this [poisonous plant](https://www.health.com/belladonna-8704956)). - **Irritant contact dermatitis** is the more common type of contact dermatitis. It's caused by repeated exposure to an irritant. Such exposures may include applied products such as deodorants, antiperspirants, soaps, or washes. To treat symptoms, avoid allergens and irritants, and wash them off the skin. Creams and medications may be necessary at times. ## 2\. Hidradenitis Suppurativa (HS) [Hidradenitis suppurativa](https://www.health.com/hidradenitis-suppurativa-treatment-7644251) (HS), also known as acne inversa, is a [chronic inflammatory skin condition](https://www.health.com/what-i-wish-i-knew-living-with-hidradenitis-suppurativa-hs-8785792). It begins as a blockage of hair follicles in areas of the body where certain sweat glands (called apocrine sweat glands) reside. In its mildest form, HS produces small, painful, pus-filled bumps. They may look reddish, purplish, or darker brown, depending on your skin color. As HS progresses, larger nodules can develop. These bumps can rupture, leaking foul-smelling fluid and pus. Tracks or tunnels can form beneath the skin, leading to scarring and keloids. Various surgical procedures may be helpful in general, but treatment often depends on the severity of the disease, which is as follows: - **Mild:** Topically applied cleansers and antibiotics - **Moderate:** Various oral medications and combination therapies - **Moderate-to-severe:** Adalimumab (Humira), an injectable biologic ## 3\. Folliculitis A zit-like rash in your armpits might be [folliculitis](https://www.health.com/folliculitis-7374055), a common condition that occurs when hair follicles become infected. You might develop it from shaving and waxing, wearing tight clothing, or taking certain medications. Treatment may depend on the type and severity of the rash. For a mild, pimply rash, it may be best to stop shaving for a couple of days and apply an over-the-counter topical steroid, like hydrocortisone cream. You may need an antibiotic for a more severe rash, such as when pustules or small whiteheads form on the bumps. ## 4\. Acanthosis Nigricans (AN) Acanthosis nigricans (AN) isn't a rash. It's a velvety thickening of the skin in the body's folds and creases, including the armpits. These patches appear darker in color than the surrounding skin. People who are overweight, have a family history of AN, or have darker skin are at greater risk of developing this skin condition. In addition, acanthosis nigricans has been linked to: - Hormonal irregularities like [thyroid disease](https://www.health.com/thyroid-disease-overview-7110516) - [Insulin resistance](https://www.health.com/insulin-resistance-7377181) due to diabetes or pre-diabetes, for example - The use of certain drugs, such as birth control pills or steroids Treatment for AN involves addressing any underlying medical cause. Providers may suggest oral or topical retinoids to clear the skin, laser treatments to reduce thickness, or topical medication to lighten the skin. ## 5\. Intertrigo Chafing, or skin rubbing against skin—especially in warm or moist areas of the body—can cause [intertrigo](https://www.health.com/mind-body/ways-prevent-thigh-rub). This results in an itchy, burning rash that may appear red or reddish-brown. These so-called intertriginous areas can ooze, crack, or bleed. As the skin breaks down, it becomes vulnerable to infection. In addition, you may develop a yeast, bacterial, or fungal underarm rash with intertrigo. Keeping skin folds cool and dry can help with healing and prevent recurrences. Treatment options include antibiotic or antifungal creams, topical steroid creams, and drying agents (such as antiperspirants or absorbent powders). ## 6\. Inverse Psoriasis Also called intertriginous [psoriasis](https://www.health.com/psoriasis-diagnosis-6835623), this type of rash affects the body's skin folds. Unlike the white, scaly patches that psoriasis usually produces, inverse psoriasis can be smooth and shiny. The rash can be sore, itchy, and irritated from sweating. Topical steroids are usually the first choice of treatment. More severe cases, however, may require oral medication or biologic therapy. ## 7\. Ringworm Ringworm is an itchy, scaly rash that forms a ring-like pattern on the skin. It belongs to a group of diseases called tinea, caused by fungi. It spreads through contact with an infected person or animal, or by touching a surface where the fungus likes to live. You can also get [ringworm](https://www.health.com/ringworm-overview-7108653) by sharing towels or other personal items with someone who has the infection. Ringworm is typically treated topically with an over-the-counter or prescription antifungal medication. ## 8\. Cutaneous Candidiasis (Yeast) Yeast thrives in warm, moist creases or folds of the body, like your armpits. Candidiasis is a yeast infection of the skin. The same fungus that causes most [vaginal yeast infections](https://www.health.com/yeast-infection-symptoms-7252894), *Candida albicans,* is often responsible for skin infections. These infections result from an overgrowth of yeast normally found on your skin. You may find this discolored rash in skin folds or due to hair follicle infections. Treatments might include using drying powders, keeping your skin dry, or applying antifungal products like creams or ointments. ## 9\. Heat Rash (Prickly Heat) You can get a pimply underarm rash from being overheated. This type of rash (also called miliaria) occurs when sweat glands and ducts become obstructed by bacteria, skin cells, oil, or other debris. Clusters of pimples or small blisters can make your skin feel itchy or irritated—causing prickly, tingling pain. A [heat rash](https://www.health.com/condition/skin-conditions/heat-rash-treatment) should still clear up on its own if you keep your skin cool and dry. In some cases, a healthcare provider may recommend a prescription lotion to reduce discomfort. ## 10\. Cutaneous Lymphoma (Skin Lymphoma) Cutaneous lymphoma, or lymphoma of the skin, is an uncommon type of cancer. It begins in white blood cells called lymphocytes, which are part of the body's immune system. [Skin lymphomas](https://www.health.com/condition/skin-cancer-overview) may appear as pimples, flat patches, thick plaques, or nodules. They may be itchy and range in color from red to purple. If cancer reaches the lymph nodes, you may feel a lump in your armpit area. Most skin lymphomas have no known cause. A weakened immune system can boost your risk of developing skin lymphoma, although it's unclear why. Various treatments may be recommended depending on the type, location, and stage of cancer. Updated by [Sarah Vanbuskirk](https://www.health.com/sarah-vanbuskirk-11772503) ![Headshot of Sarah Vanbuskirk]() :max_bytes\(150000\):strip_icc\(\)/Headshot-SarahVanbuskirk-d6786f7e39fb4085b5f6fa95dca9a2e1.png) [Sarah Vanbuskirk](https://www.health.com/sarah-vanbuskirk-11772503) Sarah Vanbuskirk is an experienced journalist and editor who has written for a wide range of local and national publications and websites. [learn more](https://www.health.com/about-us-8415145) Read more: - [Health Conditions A-Z](https://www.health.com/diseases-conditions) - [Skin, Hair & Nail Conditions](https://www.health.com/condition/skin-conditions) Was this page helpful? Thanks for your feedback\! Tell us why\! Other 22 Sources Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our [editorial process](https://www.health.com/health-com-s-editorial-process-5224046) to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. 1. Medline Plus. [Contact dermatitis](https://medlineplus.gov/ency/article/000869.htm). 2. American Academy of Dermatology. [Eczema types: contact dermatitis signs and symptoms](https://www.aad.org/public/diseases/eczema/types/contact-dermatitis/symptoms). 3. Medline Plus. [Hidradenitis suppurativa](https://medlineplus.gov/genetics/condition/hidradenitis-suppurativa/). 4. American Academy of Dermatology. [Hidradenitis suppurativa: signs and symptoms](https://www.aad.org/public/diseases/a-z/hidradenitis-suppurativa-symptoms). 5. Singer E, Kundu R. [Hidradenitis suppurativa with extensive secondary keloid formation](https://doi.org/10.1016/j.jaad.2017.04.594). *Journal of the American Academy of Dermatology*. 2017;76(6):AB153. doi:10.1016/j.jaad.2017.04.594 6. American Academy of Dermatology. [Hidradenitis suppurativa: diagnosis and treatment](https://www.aad.org/public/diseases/a-z/hidradenitis-suppurativa-treatment). 7. American Academy of Dermatology. [Acne-like breakouts could be folliculitis](https://www.aad.org/public/diseases/a-z/folliculitis). 8. Maderal AD. [Acanthosis nigricans](https://www.uptodate.com/contents/acanthosis-nigricans). In:*UpToDate.* UpToDate; 2023. 9. American Academy of Dermatology. [Acanthosis nigricans: who gets and causes](https://www.aad.org/public/diseases/a-z/acanthosis-nigricans-causes). 10. American Association of Dermatology. [Acanthosis nigricans: diagnosis and treatment](https://www.aad.org/public/diseases/a-z/acanthosis-nigricans-treatment). 11. MedlinePlus. [Intertrigo](https://medlineplus.gov/ency/article/003223.htm). 12. American Academy of Family Physicians. [Intertrigo](https://familydoctor.org/condition/intertrigo/). 13. National Psoriasis Foundation. [Inverse psoriasis](https://www.psoriasis.org/inverse-psoriasis/). 14. Merola, JF, Qureshi, A, Husni, ME. [Underdiagnosed and undertreated psoriasis: Nuances of treating psoriasis affecting the scalp, face, intertriginous areas, genitals, hands, feet, and nails](https://doi.org/10.1111/dth.12589). *Dermatologic Therapy*. 2018; 31:e12589. doi:10.1111/dth.12589 15. MedlinePlus. [Tinea infections](https://medlineplus.gov/tineainfections.html). 16. Centers for Disease Control and Prevention. [What causes ringworm and fungal nail infections](https://www.cdc.gov/ringworm/causes). 17. MedlinePlus. [Candida infection of the skin](https://medlineplus.gov/ency/article/000880.htm). 18. Guerra KC, Toncar A, Krishnamurthy K. [Miliaria](https://www.ncbi.nlm.nih.gov/books/NBK537176). In:*StatPearls.* StatPearls Publishing; 2022. 19. American Academy of Family Physicians. [Heat rash](https://familydoctor.org/condition/heat-rash/). 20. American Cancer Society. [About lymphoma of the skin](https://www.cancer.org/cancer/skin-lymphoma/about.html). 21. American Cancer Society. [Signs and symptoms of skin lymphoma](https://www.cancer.org/cancer/types/skin-lymphoma/detection-diagnosis-staging/signs-and-symptoms.html). 22. American Cancer Society. [What causes lymphoma of the skin?](https://www.cancer.org/cancer/skin-lymphoma/causes-risks-prevention/what-causes.html) ## Related Articles [![Doctor examining patient's face]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-1393811822-f35f287730724246b270c5e05ed6538a.jpg) 16 Skin Rash Types: Pictures, Causes, and Treatment](https://www.health.com/skin-rash-7372022) [![Person itching rash on neck]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-1470737785-674dd74231e44187b345c29869170965.jpg) Why Do You Have a Rash on Your Neck?](https://www.health.com/rash-on-neck-8699942) [![Close up of person scratching their neck where a small rash is.]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-1765432668-00434bbc48ed43f691b4bd9cc5a9aca5.jpg) Everything You Need To Know About an Allergy Rash](https://www.health.com/condition/allergy/allergy-rash) [![Person putting sunscreen on arm, sun rash]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-1533190032-28b09365a426418693a9ebaead341f70.jpg) What Is a Sun Rash?](https://www.health.com/sun-rash-8620019) [![Middle-aged woman with her back turned inside a swimming pool]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-1363129479-f756fd107c7249b3a9b7867318cc8c8d.jpg) Chlorine Rash: Causes, Symptoms, and Prevention Tips](https://www.health.com/condition/skin-conditions/chlorine-rash) [![Dermatologist examining rash on patient's back]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-2155223391-218aa50778f74f31bdb0cc0613de04e7.jpg) What To Know about Grover's Disease](https://www.health.com/grovers-disease-8677612) [![Closeup of a person adjusting a shirt sleeve outdoors blue sky in the background]() :max_bytes\(150000\):strip_icc\(\)/Health-GettyImages-1431427573-460674b6794540559d78fd6b3ffdda15.jpg) Why Do My Armpits Sweat So Much? 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Armpit rashes can develop from infections, allergies, or irritation. Symptoms range from mild itching to severe inflammation. [buraratn](https://www.gettyimages.com/search/photographer?photographer=buraratn) / Getty Images This rash is caused by exposure to an irritant or an allergen. [Contact dermatitis](https://www.health.com/contact-dermatitis-7377965) has two main types, each causing an itchy, burning, or painful rash: - **Allergic contact dermatitis** occurs when the skin comes in contact with a substance that provokes an immune response. Your rash could be an allergic reaction to fragrances, preservatives in soap and skin products, or [poison ivy](https://www.health.com/condition/skin-conditions/home-remedies-for-poison-ivy) (presuming you recently had a brush with this [poisonous plant](https://www.health.com/belladonna-8704956)). - **Irritant contact dermatitis** is the more common type of contact dermatitis. It's caused by repeated exposure to an irritant. Such exposures may include applied products such as deodorants, antiperspirants, soaps, or washes. To treat symptoms, avoid allergens and irritants, and wash them off the skin. Creams and medications may be necessary at times. [Hidradenitis suppurativa](https://www.health.com/hidradenitis-suppurativa-treatment-7644251) (HS), also known as acne inversa, is a [chronic inflammatory skin condition](https://www.health.com/what-i-wish-i-knew-living-with-hidradenitis-suppurativa-hs-8785792). It begins as a blockage of hair follicles in areas of the body where certain sweat glands (called apocrine sweat glands) reside. In its mildest form, HS produces small, painful, pus-filled bumps. They may look reddish, purplish, or darker brown, depending on your skin color. As HS progresses, larger nodules can develop. These bumps can rupture, leaking foul-smelling fluid and pus. Tracks or tunnels can form beneath the skin, leading to scarring and keloids. Various surgical procedures may be helpful in general, but treatment often depends on the severity of the disease, which is as follows: - **Mild:** Topically applied cleansers and antibiotics - **Moderate:** Various oral medications and combination therapies - **Moderate-to-severe:** Adalimumab (Humira), an injectable biologic A zit-like rash in your armpits might be [folliculitis](https://www.health.com/folliculitis-7374055), a common condition that occurs when hair follicles become infected. You might develop it from shaving and waxing, wearing tight clothing, or taking certain medications. Treatment may depend on the type and severity of the rash. For a mild, pimply rash, it may be best to stop shaving for a couple of days and apply an over-the-counter topical steroid, like hydrocortisone cream. You may need an antibiotic for a more severe rash, such as when pustules or small whiteheads form on the bumps. Acanthosis nigricans (AN) isn't a rash. It's a velvety thickening of the skin in the body's folds and creases, including the armpits. These patches appear darker in color than the surrounding skin. People who are overweight, have a family history of AN, or have darker skin are at greater risk of developing this skin condition. In addition, acanthosis nigricans has been linked to: - Hormonal irregularities like [thyroid disease](https://www.health.com/thyroid-disease-overview-7110516) - [Insulin resistance](https://www.health.com/insulin-resistance-7377181) due to diabetes or pre-diabetes, for example - The use of certain drugs, such as birth control pills or steroids Treatment for AN involves addressing any underlying medical cause. Providers may suggest oral or topical retinoids to clear the skin, laser treatments to reduce thickness, or topical medication to lighten the skin. Chafing, or skin rubbing against skin—especially in warm or moist areas of the body—can cause [intertrigo](https://www.health.com/mind-body/ways-prevent-thigh-rub). This results in an itchy, burning rash that may appear red or reddish-brown. These so-called intertriginous areas can ooze, crack, or bleed. As the skin breaks down, it becomes vulnerable to infection. In addition, you may develop a yeast, bacterial, or fungal underarm rash with intertrigo. Keeping skin folds cool and dry can help with healing and prevent recurrences. Treatment options include antibiotic or antifungal creams, topical steroid creams, and drying agents (such as antiperspirants or absorbent powders). Also called intertriginous [psoriasis](https://www.health.com/psoriasis-diagnosis-6835623), this type of rash affects the body's skin folds. Unlike the white, scaly patches that psoriasis usually produces, inverse psoriasis can be smooth and shiny. The rash can be sore, itchy, and irritated from sweating. Topical steroids are usually the first choice of treatment. More severe cases, however, may require oral medication or biologic therapy. Ringworm is an itchy, scaly rash that forms a ring-like pattern on the skin. It belongs to a group of diseases called tinea, caused by fungi. It spreads through contact with an infected person or animal, or by touching a surface where the fungus likes to live. You can also get [ringworm](https://www.health.com/ringworm-overview-7108653) by sharing towels or other personal items with someone who has the infection. Ringworm is typically treated topically with an over-the-counter or prescription antifungal medication. Yeast thrives in warm, moist creases or folds of the body, like your armpits. Candidiasis is a yeast infection of the skin. The same fungus that causes most [vaginal yeast infections](https://www.health.com/yeast-infection-symptoms-7252894), *Candida albicans,* is often responsible for skin infections. These infections result from an overgrowth of yeast normally found on your skin. You may find this discolored rash in skin folds or due to hair follicle infections. Treatments might include using drying powders, keeping your skin dry, or applying antifungal products like creams or ointments. You can get a pimply underarm rash from being overheated. This type of rash (also called miliaria) occurs when sweat glands and ducts become obstructed by bacteria, skin cells, oil, or other debris. Clusters of pimples or small blisters can make your skin feel itchy or irritated—causing prickly, tingling pain. A [heat rash](https://www.health.com/condition/skin-conditions/heat-rash-treatment) should still clear up on its own if you keep your skin cool and dry. In some cases, a healthcare provider may recommend a prescription lotion to reduce discomfort. Cutaneous lymphoma, or lymphoma of the skin, is an uncommon type of cancer. It begins in white blood cells called lymphocytes, which are part of the body's immune system. [Skin lymphomas](https://www.health.com/condition/skin-cancer-overview) may appear as pimples, flat patches, thick plaques, or nodules. They may be itchy and range in color from red to purple. If cancer reaches the lymph nodes, you may feel a lump in your armpit area. Most skin lymphomas have no known cause. A weakened immune system can boost your risk of developing skin lymphoma, although it's unclear why. Various treatments may be recommended depending on the type, location, and stage of cancer.