Armpit rashes often develop due to allergic reactions, infections, and chronic conditions.
Rashes are common under the arms because the skinfold creates a warm, moist environment.
Additionally, the skin can chafe easily and the armpit has hair follicles and sweat glands.
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These factors make the perfect conditions for numerous types of rashes.
Here are the 12 most common types of underarm rashes.
Allergic Contact Dermatitis
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Allergic reactions commonly cause an armpit rash.
Allergiccontact dermatitisoccurs when an allergy-triggering substance (allergen) comes into contact with the skin.
Treatment:Treatment begins by identifying the allergen and avoiding it.
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You may be able to rule out personal care products and switching to another brand.
If you have a severe rash, you may need prescription medications.
Irritant Contact Dermatitis
Armpit rashes can also be due to irritant contact dermatitis.
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In this case, you don’t have an allergic reaction.
Instead, the rash is the direct of an irritant or toxin touching the skin.
Common irritants include deodorants, antiperspirants, soaps, and body washes.
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The rash appears discolored, rough, or scaly.
In severe cases, it can cause blisters.
Once you know what irritant is causing the rash, you’re free to avoid it.
If your symptoms are severe or not getting better, it’s important to let your provider know.
Can Eczema Cause Armpit Rashes?
Allergic and contact dermatitis are forms ofeczemathat can develop under your arms.
The rashes may develop dry, scaly patches or blisters that can leak fluid (weeping eczema).
Folliculitis
Hair follicles in your armpit can get irritated, blocked, or infected.
As a result, inflammation and a pimple-like rash (folliculitis) develop.
This gives the follicles time to heal.
Warm compresses can also ease the itch and promote healing.
Consult your healthcare provider if the rash doesn’t improve or worsens.
You may need a prescription medication to treat an infection.
Heat, moisture, and chafing in the skinfold cause inflammation and a rash.
These germs trigger your immune system to react, which leads to skin inflammation and rash.
You may also need antibiotics or antifungals to fight the organisms that caused the rash.
Yeast Infections
Your armpit rash may be triggered by ayeast infection(candidiasis).
Yeast naturally live on your skin.
Yeast infections cause an itchy, bright red rash, possibly with oozing patches.
In some cases, the yeast may also infect the follicle, resulting in a pimple-like rash.
Depending on the skin tone, the rash is reddish or darker colored.
You may have scaly patches and the mild itching.
The rash may cause slight skin wrinkling.
Treatment: Erythrasma is typically treated with antibiotics, either a topical or oral tablet.
Your healthcare provider may recommend cleaning the patches with an antibacterial soap.
Laser treatment may help if the rash doesn’t improve with medication.
For example, when it’s in the underarm or behind the knee, it’s called tinea corporis.
If it’s on the foot, it’s calledtinea pedis(or “athlete’s foot”).
When it shows up in the groin, it’s calledtinea cruris(or “jock itch”).
The rash from ringworm has raised borders that may have a thin layer of scales.
On lighter skin tones, the rash usually looks red.
The key feature of a ringworm rash is that it expands, growing outward in a circle.
Ringworm can also be itchy and makes the hair on the affected area of the skin fall out.
Treatment:Ringworm is treated with topical antifungal medications, which are available at the pharmacy.
Inverse Psoriasis
Inverse psoriasisis a form ofpsoriasisthat often appears under your arm.
Friction between the skin in your armpit may trigger inverse psoriasis.
However, infections, skin injuries, and certain medications can cause the rash.
Unlike plaque psoriasis, the red rash from inverse psoriasis is usually smooth and shiny and doesnt have scales.
It may look brown or tan on darker skin tones.
Treatment: The treatment for inverse psoriasis includes topical medications, whether steroids or one of several remedies.
In this condition, hair follicles near sweat glands get blocked and irritate the skin.
The rash consists of painful bumps that have pus in them.
The pus may causes an odor if it leaks.
Over time, recurrent rashes can scar the skin.
Treatment:Your healthcare provider may start your treatment with OTC topical medications.
If the rash is severe, you may need prescription medications.
Or, your healthcare provider may need to drain the bumps if they’re large and painful.
As a result, the area becomes irritated, your skin turns red, and itchy bumps appear.
Consult your healthcare provider if the rash is severe or doesn’t improve in a few days.
Can You Get Cancer In Your Armpit?
Instead, the condition causing it must be treated.
Once the underlying condition is under control, the rash should get better.
Syphilis
Syphilisis a sexually transmitted bacterial illness.
Without treatment, syphilis progresses through three stages.
A syphilis rash can appear anywhere on the body, including your armpit.
Penicillin is the preferred treatment for syphilis.
Prevention
Most armpit rashes can be prevented with self-care strategies.
They can make a diagnosis and recommend the best treatment.
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