There are many causes of underarm rashes, including irritation and chafing, eczema, and ringworm. A healthcare professional can provide a diagnosis and recommend appropriate treatment.
The cause of and treatment for an underarm rash may depend on factors such as the appearance, extent, and duration of the rash. In some cases, a rash is a temporary symptom that may improve with over-the-counter (OTC) medications and home remedies.
However, some rashes, such as long lasting, returning, or severe rashes, can indicate an underlying health condition requiring medical attention and treatment.
This article examines different types of armpit rashes and explains the treatment options for each one.
There are many different causes of armpit rash. The most common ones are listed below:
Irritation can occur when skin rubs hard against itself or clothing for too long. Areas of the body where the skin folds over or rubs against itself frequently, such as the armpit, are especially prone to chafing.
Chafing rashes are usually:
- raw, or with the top layer of skin rubbed off
- stinging and burning
- in streak formations, often with a lighter center streak
- swollen, cracked, bleeding, or crusted if severe
People may experience underarm chafing while exercising or wearing clothing that does not fit properly.
People may also experience chafing during the spring and summer months because they sweat more in the heat, and moist skin is quicker to irritate.
Heat can mix with sweat on the skin and cause an irritation rash known as heat rash.
In most cases, heat rash causes itchy patches of bumps that are:
- slightly raised
People may develop heat rash in their armpits during the warmer months or while in hot climates because the armpits contain lots of sweat glands.
Contact dermatitis occurs when the skin or body encounters an allergen or irritant, sparking an immune response. This allergic reaction usually develops within a few hours of exposure to allergens or irritants.
Contact dermatitis rashes are usually:
There are many different triggers of contact dermatitis. Some of the most common include:
- chemicals found in cleaning detergents and personal care products
- food or environmental allergens
- insect stings or bites
Hair removal processes
People can develop patches of tiny, red, painful bumps after shaving their underarms. These bumps are usually present in and around the hair follicles.
Eczema patches are usually:
- prone to releasing clear fluid after scratching
An armpit rash may occur alongside similar patches on other body parts, such as the elbows, back of the knees, and neck.
People with eczema may experience flare-ups during certain times of the year or when they are ill or experiencing stress.
Seborrheic dermatitis is a type of eczema that develops around oil-producing glands. It causes symptoms that are different from those of eczema.
Seborrheic dermatitis rashes are usually:
- greasy looking
- itchy and burning
The skin may also develop white or yellow flakes.
A type of yeast called Candida
Ringworm is a fungal infection that causes a red or silver ring-like rash.
Ringworm rashes may also be:
- blistered or scabbed
The best treatment option for an armpit rash will depend on the cause of the rash.
Rashes that occur as a result of allergic reactions or general skin irritation may respond to home care. People with these types of rashes can try the following remedies:
- Keep the area cool and dry by wearing loose clothing and taking lukewarm showers.
- Stay out of the sun as much as possible and away from humid environments.
- Tap or pat itchy skin gently instead of scratching it.
- Take a lukewarm bath with added oatmeal, vinegar, salt, or baking soda.
- Apply unscented moisturizers to dry, scaly rashes several times a day.
- Avoid long periods in water, including long showers or baths.
Some natural therapies and supplements may also help reduce or treat most armpit rashes, but it is worth noting that there is little scientific evidence supporting their use.
- coconut oil
- topical vitamin B12
- sunflower oil
- supplements, such as vitamin D
- stress reduction, including massage
Some conditions that cause armpit rashes may respond to treatment using OTC medications. OTC remedies for allergic reactions and other skin irritations include:
- hydrocortisone creams
- antihistamine medications
- calamine lotions or creams
- antifungal creams, gels, or sprays
People should speak with a healthcare professional about the most appropriate OTC treatment options for their rash.
Armpit rashes that appear due to chronic skin conditions may require medical treatment. However, a doctor may recommend a mixture of OTC and at-home remedies before prescription medications.
Prescription treatment options for people with eczema include:
- topical steroid creams
- topical PDE4 inhibitors
- topical calcineurin inhibitors
- biologic medications that contain engineered versions of human immune proteins
Seborrheic dermatitis treatment
Treatment options for people with seborrheic dermatitis include:
- applying OTC antifungal creams
- skin-softening treatments, such as coal tar
- topical corticosteroids
- antibiotic ointments
Understanding what causes armpit rashes may help minimize their severity. General tips for preventing underarm rashes include:
- identifying and avoiding allergens where possible
- using unscented and fragrance-free personal care products
- bathing regularly in lukewarm water but not for extended periods
- using anti-chafing powders when in warm weather or exercising
- wearing clothing and undergarments that fit properly
- washing clothing, bedding, and towels frequently
- washing the hands or body after being around soil, animals, and plants
- avoiding sharing towels, combs, or clothing with other people
With proper care, most armpit rashes do not cause any complications. Without this care, however, scarring and infection may develop. Scarring may occur if people scratch their rash too much or following an infection.
Chronic or severe rashes, or those that do not go away with home treatment, may have a broader range of complications.
For example, around 80% of children with eczema may develop conditions such as asthma and allergic rhinitis.
People with a severe or chronic rash or one that does not improve with home remedies should always talk with a doctor as soon as possible to determine its cause and potential treatment options.
Certain types of rashes result from medical conditions that require emergency treatment, such as severe infection or allergic reactions.
Seek emergency medical care for rashes that:
- cover the entire body or most of it
- are accompanied by blisters or fever
- develop suddenly and spread rapidly
- are painful or swollen
- bleed, ooze, or release pus
- are around the genitals, mouth, or eyes
- accompany nausea, vomiting, diarrhea, or constipation
- are unresponsive to OTC or home remedies
- sit in areas of thickened, crusty, or scabbed skin
- are in the midst of painful, tender, swollen, or red skin
- occur alongside cold hands and feet
- appear when the body is shaking
- are present alongside a stiff neck
- accompany confusion or dizziness
Below are the answers to some common questions about armpit rashes.
What does a deodorant rash look like?
Some people may experience contact dermatitis after applying certain deodorants. Symptoms may include a red, dry, itchy, or blistered rash on the skin where they applied deodorant.
How can someone tell if an armpit rash is fungal?
The specific symptoms of a fungal rash may depend on the cause of the infection. However, the skin may be itchy, swollen, and scaly.
What does a rash under your armpit mean?
Causes of an underarm rash include chafing, heat rash, and allergic reactions. Conditions like eczema, ringworm, and dermatitis can also cause it.
How do I get rid of a rash under my armpits?
The best treatment option for an armpit rash will depend on the cause of the rash. For allergies and general skin irritation, people can try home remedies and OTC medication. Rashes caused by chronic skin conditions often require prescription medication.
An armpit rash may occur due to friction, irritation, or infection. The specific symptoms someone experiences may depend on the cause of the rash.
Some rashes may respond to home remedies or OTC medications. However, people should speak with a doctor if the rash does not improve or if signs of infection develop.
A doctor can diagnose the cause of the rash and prescribe appropriate treatment, such as corticosteroids.