Why Is There a Rash Under My Armpit? Everything You Want to Know About Underarm Rash

    Updated 27 November 2021 |
    Published 01 November 2019
    Fact Checked
    Reviewed by Andrej Vitushka, MD, PhD, Neonatal Intensive Care Specialists, Medical Consultant at Flo
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    If you’ve ever experienced a rash on your armpit, you know that it can be uncomfortable and may make you feel self-conscious. Read on to discover more about the causes and treatment of this common condition.

    How to diagnose underarm rash 

    If you’re like most people, you probably don’t spend a lot of time thinking about your armpits. But if you’re experiencing a rash there, it may be hard to think about anything else.

    Many people don’t realize how common it is for the skin in this area to become irritated. Armpit rash is often concealed beneath clothing, but just because you can’t see it doesn’t mean it can’t cause a lot of discomfort and itching.

    If you have an armpit rash, you may find it easiest to examine your skin in front of a mirror. This type of irritation varies in appearance: the color may be red or white, and the texture may be bumpy or scaly.

    There’s no reason to feel embarrassed or self-conscious about an armpit rash. This is a very common condition that affects people of all ages.

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    Causes of an armpit rash

    There are a number of potential causes of an underarm rash. The recommended treatment will depend upon the cause. The duration of a rash also varies according to the cause: short-term rashes may improve in hours or days, but others may last weeks or even months.

    Although many armpit rashes can be effectively treated using home remedies or over-the-counter medications from your drugstore or pharmacy, it’s still important to consult a trusted healthcare professional about it. They will be in the best position to diagnose and treat your specific rash.

    Here are some common causes of armpit rash:

    • Heat rash is a very common and straightforward cause of underarm rash. It’s usually caused by hot weather and tight-fitting synthetic clothing that allows sweat to pool on the body. Heat rash often appears as small white bumps on the skin. This type of rash usually resolves quickly once the body has cooled down and doesn’t cause any itching.
    • Eczema — or atopic dermatitis — is another common cause of irritation on the armpit. This skin condition is usually diagnosed in childhood and typically affects the armpits and the backs of the knees. It appears as a red, scaly rash that can be itchy.
    • Contact dermatitis is another frequent cause of armpit rash. It occurs when your skin makes contact with an irritant or allergen. This can include soap, detergent, or even fabric. Contact dermatitis may cause both redness and blistering in the area of the irritation.
    • Psoriasis is a chronic skin condition that results from an overactive immune response. It causes flaky, inflamed skin that often presents as thick white patches.
    • Candida is a yeast that causes irritation in moist areas of the body, such as skin folds, armpits, and the groin. Poor hygiene and hot weather can increase the likelihood of this type of infection. It usually has a red, scaly appearance and may also itch.

    How to treat underarm rash

    Since armpit rashes have many causes, it’s really important to determine the specific cause of the rash. This will put you in the best position to decide on the most appropriate treatment.

    If you’re unable to figure out what has caused your particular rash, it’s best that you seek the advice of a trusted medical professional. They will be able to suggest the most effective treatment.

    Your doctor or other medical provider may suggest any one of the following options:

    • A wide variety of over-the-counter medications are available at drugstores and pharmacies. These work in different ways, but many include a mild anesthetic or other soothing medicine that will reduce discomfort and itchiness. You can also find hydrocortisone or other steroid preparations that help with inflammation and antihistamines that reduce itching.
    • Eczema is commonly treated with hydrating and lubricating ointments and creams, topical steroids, and other preparations that reduce inflammation.
    • Psoriasis is also treated with steroid creams, alongside a number of other therapies.
    • A candida rash or other type of local yeast infection is usually treated with an antifungal medication. Look for products that include ingredients like clotrimazole or ketoconazole. Avoid hydrocortisone creams as they may worsen a candida infection.

    In addition to these options, you may find the following over-the-counter treatments and home remedies can ease the discomfort of an armpit rash:

    • You may find that a warm bath helps to soothe the irritation that can result from an armpit rash. Be careful to avoid excessively hot water that may further irritate the skin. You may also consider adding a skin-calming oatmeal preparation to your bath.
    • Sometimes cool compresses also provide relief.
    • In some cases, the discomfort of a skin rash can be worsened by dry skin in this area. If this is the case, consider applying a scent-free moisturizer that is suitable for sensitive skin.

    How to prevent an armpit rash under the armpits

    In addition to the above treatment options, there are a number of steps you can take to prevent skin irritation in the first place.

    Keep the following tips in mind:

    • If you’re suffering from contact dermatitis in your armpit, one of the simplest and most effective ways to treat it is to avoid contact with the irritant that caused the rash. If you’ve just started using a new deodorant or detergent, it may be pretty easy to identify and eliminate the cause of the rash, otherwise you may need to do a little detective work to find the culprit!
    • Although it can be very hard to resist, do your best to avoid scratching the skin. It may offer temporary relief from itching, but you’re likely to increase irritation and risk of infection.
    • Many people are unaware that stress is a very important factor in overall skin health. You may have noticed that your skin reacts poorly when you are under a lot of pressure or sleep-deprived. You may be able to improve your skin condition by practicing relaxation techniques and improving your sleeping habits.

    When to see a doctor

    If your armpit rash doesn’t resolve after trying a few of the suggested treatments and lifestyle changes, then it’s time to consult a medical professional.

    Wrapping up

    There are many causes of armpit rashes, but most can be effectively treated using a combination of medications and lifestyle changes.

    One of the best ways to avoid skin rashes is to practice good hygiene. Shower frequently and air-dry your body rather than using a towel.

    Avoid skincare and cosmetic products that irritate your skin and try to wear loose-fitting cotton clothing that allows your skin to breath and encourages sweat to evaporate.

    History of updates

    Current version (27 November 2021)

    Reviewed by Andrej Vitushka, MD, PhD, Neonatal Intensive Care Specialists, Medical Consultant at Flo

    Published (01 November 2019)

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