Read Full Article HereAn armpit rash can be uncomfortable or even painful. Often, the cause is mysterious but no cause for concern. But sometimes, an armpit rash is severe enough to require a trip to the doctor.
Learn what causes armpit rash, how it’s diagnosed, and treatment options.
Where Does an Armpit Rash Typically Develop?
Armpit rash can develop in the armpits themselves or in the skin around the underarm area. The rash may appear red or darker than your natural skin tone, be raised or flat, or have pimple-like bumps. It can be wet or dry, and it may ooze fluids.
The armpits are susceptible to rash, as they contain apocrine sweat glands, a type of sweat gland that produces an odor.[1] At the same time, the armpits can get closed off and dark, making it easy for sweat and oil to accumulate in the folds of the skin. “Armpits can be notoriously warm and moist areas and subject to repeated friction from moving one’s arms about,” says Neil Farnsworth, MD, staff dermatologist at Westlake Dermatology River Oaks in Houston, Texas. “These factors set the stage for a range of possible rashes.”
What Causes an Armpit Rash?
There are many potential causes of armpit rash, including:
Friction Dermatitis
Friction dermatitis is a common type of rash. Also known as chafing, the friction created by skin rubbing on skin or clothing can cause irritation.
Heat and excess sweating can contribute to chafing, as can shaving, which removes skin, making your underarms more vulnerable to damage from rubbing, adds Kathryn Durham, MD, a board-certified dermatologist with U.S. Dermatology Partners in Fort Worth, Texas.
Contact Dermatitis
There are two types of contact dermatitis: irritant contact dermatitis and allergic contact dermatitis.
Irritant contact dermatitis occurs when the skin barrier is disrupted by an ingredient in a product, such as cleansers, deodorants, or even clothing, Dr. Farnsworth says.
Meanwhile, allergic contact dermatitis takes place when your immune system reacts to an ingredient, leading to a rash.
It can be tough to distinguish between the two types of contact dermatitis, as they can look the same. And, often, the same ingredients, such as fragrance or preservative, are the culprits behind either type of contact dermatitis, says Farnsworth.
Fungal Infection
Excess moisture from sweat encourages an overgrowth of yeast called Candida albicans, leading to a yeast infection. “Yeast infections are often bright red, with bright bumps and pustules at the periphery, and often have a pungent ‘cheesy’ smell,” Farnsworth says.
Ringworm is another fungal infection (caused by fungi Trichophyton, Microsporum, or Epidermophyton). It can be spread by skin-to-skin contact or sharing things that touch your skin, like a towel.[2]
Hidradenitis Suppurativa
Hidradenitis suppurativa is a skin condition that features painful lumps in your skin.
Hidradentitis suppurativa is more common in Black individuals compared to those of other races and affects women more often than men.[3]
Folliculitis
Shaving sets the stage for folliculitis, a condition where bacteria enter hair follicles, causing them to become infected and inflamed, says Dr. Durham.
Anyone can develop folliculitis, but it can be more common in people who are overweight, have obesity, or type 2 diabetes. Sweating without showering or changing clothes, or spending time in hot tubs or saunas, also encourages folliculitis.[4]
Atopic Dermatitis (Eczema)
This inflammatory skin condition — which can be genetic — can also show up in the armpits. “Eczema loves skin folds, and armpits are one spot we might see it,” says Durham.
Inverse Psoriasis
A specific type of psoriasis, this condition leads to a painful rash in skin folds like the underarms, which see a lot of friction, says Durham.
Anyone can get inverse psoriasis, but you may be more susceptible if you drink alcohol, smoke, experience stress, have a vitamin D deficiency, have a relative with psoriasis, or have obesity.[5]
Syphilis
Symptoms of this sexually transmitted infection (STI) begin as sores on the penis or vagina and can progress to skin rash, fever, swollen lymph glands, weight loss, and fatigue.[6] A syphilis rash can appear as raised or flat, smooth growths that may ooze — it can also occur in your armpits.[7]
Some Cancers
Armpit rash is a fairly rare symptom of some cancers, but there are links.
Extramammary Paget’s disease (EMPD), a rare skin condition that may be associated with cancer, can show up as a persistent red, scaly, or itchy rash in the armpit.[8] While also rare, red, raised bumps in the armpit that don’t resolve may be a sign of cutaneous lymphoma (lymphoma of the skin), particularly in those with a history of cancer.[9] Finally, inflammatory breast cancer (a rare but more aggressive form of breast cancer) may cause the lymph nodes (small glands that help your body fight off infections) in the armpits to swell, creating a rash-like appearance.[10]
Is an Armpit Rash Serious?
Many underarm rashes are harmless (though often uncomfortable). You can use the conservative treatment methods outlined below (using a topical ointment, avoiding irritating ingredients), but if your symptoms don’t improve — or they get worse — make an appointment with a doctor. A dermatologist is an expert in all things skin, but your primary care provider can also diagnose an underarm rash.
An armpit rash can be serious if you have hidradenitis suppurativa, says Farnsworth. The lumps can develop abscesses or pus pockets, leading to scarring or painful, pus-filled tunnels forming under the skin. Over time, scars that form in the armpit can impair your arm’s range of motion, and the condition can be very painful.[3] If you have symptoms of hidradenitis suppurativa — a tender, deep lump in your armpit (or other areas of the body, such as underneath a breast, genitals, buttocks, or inner thighs) — see a dermatologist.[15]
Do I Need a Diagnosis for Armpit Rash?
An armpit rash is pretty unmistakable. Many causes of underarm rash do not need a doctor’s diagnosis and you can treat them at home. These include instances where you’ve identified the cause, such as chafing or allergies.
However, if you have painful bumps, an infection, or fever; notice an odor coming from your underarm; or you generally don’t feel well due to the rash, that would be the time to contact a healthcare provider to get checked out, says Durham.
For diagnosis, your provider will talk to you about your medical history and symptoms, conduct a visual examination of your rash, and may opt to do additional testing, like a patch test, blood test, or biopsy.[16]
How to Treat an Armpit Rash
Many armpit rashes can be treated at home. Farnsworth recommends trying these measures before seeking other options:
- Apply skin-healing ointment. Diaper rash ointment that contains zinc oxide helps treat and protect delicate underarm skin from irritation to encourage healing. Petroleum jelly is another good product to apply to your underarms, as it helps soothe skin, says Durham. Apply this after showering and throughout the day.[17]
- Avoid skin-irritating ingredients. Check the ingredient label of any skin-care product that comes in contact with your underarms, including deodorants/antiperspirants, body wash, lotion, and even shampoo. Quit using any products that include fragrances, preservatives, and propylene glycol. These three ingredients are common culprits of underarm rash.
If those two measures don’t help or your rash worsens, see your primary care provider or a board-certified dermatologist, Farnsworth says. They can diagnose a rash or underlying skin condition and prescribe medications, such as topical or oral antibiotics or anti-yeast or anti-inflammatory agents, to treat the irritation, he says.
Are There Complications Related to Armpit Rash?
Some rashes can cause complications, depending on the underlying cause. For example, hidradenitis suppurativa can limit your arm’s range of motion and may require surgery to drain a painful, pus-filled bump.[3] Meanwhile, a folliculitis infection, which is usually mild, can spread to nearby areas or cause a scar if left untreated.[18] In other cases, underlying causes of an armpit rash — not the rash itself — such as syphilis, can lead to complications (such as organ damage) if it’s not diagnosed and treated.[19]
Prevention
You can do things in and out of the shower to care for your underarm skin and help prevent rashes.
First, wash with an antibacterial soap and gently exfoliate with a body brush, recommends Durham. “Use the brush one to three times per week, depending on sweat and activity level. It reduces bacteria and gets all of the products off to give skin a fresh start when we apply deodorant or antiperspirant,” she explains.
Wearing breathable clothing, changing out of sweaty clothes, and washing sweat promptly off your skin can also prevent pit problems.
The Takeaway
Underarms are vulnerable to rash because they are a dark, moist environment that rubs against skin and clothing. Most armpit rashes are mild and go away with skin-care measures, like applying a zinc oxide ointment and avoiding potentially irritating ingredients like fragrances and preservatives in products that touch the underarms. If simple measures don’t improve the rash and you experience additional symptoms (like fever), contact your healthcare provider.
