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One moment you’re living your best life, going back and forth to work, Googling Iliza Shlesinger tour dates and making brunch plans. The next? You wake up with a rash under your boobs that feels like you’ve been singled out to test-drive a new plague.

Itchy, red, sore skin rashes are never fun, especially when they’re around the showgirls. There are many explanations for what could be going on, ranging from mild to severe.

Here’s a rundown of causes, home-remedies, and when to seek medical attention.

Possible causes include:

  • pregnancy or breastfeeding
  • mastitis
  • infections (bacterial, fungal, or yeast)
  • heat rash
  • psoriasis
  • eczema
  • viral infections (shingles)
  • abscess
  • scabies
  • hives
  • allergic or irritant contact dermatitis
  • breast cancer

Pregnancy

Hormonal changes, heat, sweat, and weight gain can all cause rashes to form between your breasts during pregnancy. However, there are also specific pregnancy-related rashes that can occur in other areas including under the breasts, such as PUPPP and prurigo.

PUPPP

Pruritic urticarial papules and plaques of pregnancy (PUPPP), is also commonly known as polymorphic eruption of pregnancy.

It’s a condition that causes small, red bumps and hive-like bumps to form on the skin, generally during your second or third trimester. It usually appears on the abdomen first, but can spread to the thighs, butt, and breasts. The good news is, it usually goes away after you give birth.

Treatment for PUPPP symptoms includes:

Important

You should always consult your doctor before using topical or oral medications during pregnancy.

Prurigo of pregnancy

Prurigo of pregnancy (also called Atopic Eruption of Pregnancy), is a condition that can occur anytime during pregnancy and essentially represents eczema (atopic dermatitis) that appears or worsens during pregnancy.

It can form in typical areas where eczema appears, usually beginning with a few itchy bumps or a scaly red rash that increases. Thought to be caused by pregnancy-related changes to the immune system, prurigo of pregnancy can last for months, even after the baby is born.

There’s no specific treatment for prurigo, but symptoms may be relieved with:

  • emollients
  • topical steroids
  • certain antihistamines
  • phototherapy

Important

As with PUPPP, always speak with your doctor before taking any oral or topical medication while pregnant.

Mastitis

Mastitis is a condition that causes inflammation and infection in breast tissue. It often occurs in women who are breastfeeding (called lactation mastitis), but can also occur in men and women who aren’t breastfeeding.

Symptoms include:

  • breasts that are tender or warm to the touch
  • breast swelling
  • thickening of breast tissue
  • breast lumps
  • continuous pain or burning sensation
  • skin redness, often in a wedge-shaped pattern
  • fever of 101°F (38°C) greater

Causes include:

Blocked milk ducts

If a breast doesn’t completely empty at feedings, milk ducts can become clogged and infected.

Bacteria entering your breast

Stagnant milk in breasts that haven’t been emptied creates an environment for bacteria to grow. Bacteria can enter your milk ducts through cracks in the skin of your nipples (#blessed), and spread from your skin’s surface or baby’s mouth.

Continuing to breastfeed is safe, and can also help clear out your milk ducts of the infection. Antibiotics and pain relievers may also be prescribed to treat the symptoms of mastitis.

If breastfeeding with mastitis, make sure to:

  • Fully empty each breast when breastfeeding.
  • Ensure your infant latches on correctly.
  • Breastfeed on the affected side first, when your baby is most hungry and will feed most strongly.
  • Vary your breastfeeding positions.
  • Wear a supportive bra.

Breast abscess

A breast abscess (aka subareolar breast abscess) is a condition that can occur if mastitis goes untreated. It’s a painful buildup of infected fluid or pus that can cause the breast to feel swollen, painful, or warm.

While abscesses usually occur in women who are breastfeeding, they can also occur in women who aren’t.

Treatments include:

  • antibiotics
  • medical draining of the abscess

Infections (bacterial, fungal, and yeast)

Candidiasis

Candidiasis is caused by the same yeast that causes vaginal yeast infections, oral thrush, and diaper rash. People who have immune system illnesses and those taking antibiotics are especially vulnerable.

Candida yeasts thrive in the warm, moist realm of the underboob. They often result in a red, itchy rash, and uncomfortable blisters or small skin cracks.

Treatments include:

  • antifungal creams
  • prescribed oral antifungal medications
  • keeping the affected areas dry

Ringworm

Despite its name, ringworm has nothing to do with worms (thankfully). It’s a type of fungal infection called tinea, in which parasitic fungi feed on dead keratin (the protein in your skin, nails, and hair). The result is round, itchy, red patches of skin with a distinctive border.

Ringworm is highly contagious. Shared towels, sheets, and showers can spread it around. It can form anywhere on the body, and can even be spread to and from your pets!

The good news is that once you begin treating it, the rash will stop growing and you’ll become less and less contagious.

Treatments include:

Cellulitis

Cellulitis is a bacterial infection that affects the deep layers of skin and tissue. Though adults usually get it in the foot or leg, it can develop nearly anywhere in the body.

The affected breast may feel:

  • swollen
  • warm
  • tender
  • painful

Other, more serious symptoms include:

  • pus-filled blisters
  • fatigue
  • fever or chills
  • cold sweats
  • nausea and vomiting
  • dizziness
  • difficulty concentrating

Important

Cellulitis can appear suddenly, progress quickly, and have potentially fatal consequences if not treated. If you think you’re showing signs of cellulitis, seek medical attention immediately.

A 7–14 day course of antibiotics is usually prescribed, and symptoms usually begin to subside after a few days.

Heat rash

A heat rash — also referred to as miliaria rubra, sweat rash, and prickly heat — happens when your sweat gland ducts become blocked.

When this happens the sweat builds up, causing a bump to form. Heat rashes are most likely to appear in places where skin touches skin, including — you guessed it — underneath your flying saucers.

The rash generally looks like small red spots or a cluster of pimples and can feel itchy.

Heat rashes can be caused by:

  • heat and humidity
  • wearing heavy or non-breathable clothing
  • intense physical activity
  • fever

The best way to treat (and avoid) heat rash is to avoid friction and keep your skin cool and dry. Cold compresses, calamine lotion, steroid creams, and cold showers are all helpful ways to alleviate symptoms.

Irritant contact dermatitis

Speaking of friction, irritant contact dermatitis is a skin condition that occurs when the skin becomes irritated by some external cause, such as excessive friction, like when two breasts rub against each other. The condition presents as red, inflamed skin.

Because sweat tends to collect in skin folds, and excessive moisture can be irritating on occluded skin, people are most likely to experience irritant contact dermatitis:

  • in the summer
  • if they have larger breasts
  • if they exercise a lot

Like heat rash, the best way to treat and prevent intertrigo is to avoid friction and keep your skin cool and dry. Zinc oxide is a great barrier that can be used in the area to prevent the irritation. Sometimes a doctor will prescribe topical steroids.

Autoimmune-related conditions

Eczema (atopic dermatitis)

Eczema is a chronic condition that involves dysfunction in the immune system and causes skin to become dry, cracked, itchy, scaly, and red. Though it usually shows up on the folds of the arms, legs and neck, it can also appear around the breasts.

Eczema triggers include:

  • weather changes, especially in winter or summer
  • soaps and detergents
  • obesity

Stress and food allergies can also trigger eczema, though this is not as typical.

The best treatment for eczema is to avoid triggers, apply plenty of moisturizers and emollients, and use antihistamines and topical steroids when necessary. Light therapy is also an option.

Inverse psoriasis

Inverse psoriasis is a less common form of psoriasis, a disorder related to immune dysfunction. It’s characterized by smooth, sometimes shiny, red lesions in the folds of the body.

Inverse psoriasis is more commonly found in those with deep skin folds.

Treatments include:

  • steroid creams
  • tar-based ointments
  • immune suppressing medications
  • topical calcineurin inhibitors like Protopic (off label)
  • topical Vitamin D analogs like calcipotriene

All treatments come with possible side effects and shouldn’t be taken without consulting your doctor.

Hyperhidrosis (excessive sweating)

Hyperhidrosis is a condition that causes excessive sweating. Sweating is necessary to cool the body, but people with hyperhidrosis sweat even when they don’t need to be cooled down.

Bottom line:

Excess sweat attracts infection-causing bacteria, and as you know by now, bacteria + moisture + skin folds = possible breast rashes.

Though the cause of hyperhidrosis is unknown, it’s thought to be hereditary — thanks Grandma Ethel.

Antiperspirants can be used to treat the symptoms of hyperhidrosis, and some are specifically made for body folds rather than underarms. Prescription-strength antiperspirants are also available. If the case is severe, doctors may suggest botox injections.

Hailey-Hailey disease

Hailey-Hailey disease has nothing to do with Eminem’s daughter or the comet — it’s a rare, inherited disorder, characterized by a chronic, blistering rash.

It often shows up on the neck, armpits, skin folds, and genitals. The rash may itch or burn and develop a crusty yellow over-layer. In time, lesions can cause painful, cracked skin.

Though the condition is genetic, symptoms are often brought on by:

  • sunlight
  • heat
  • sweating
  • friction

Hailey-Hailey disease is difficult to treat but is sometimes treated with antibiotics and corticosteroid cream.

Viral infections

Shingles

Anyone who has ever had chickenpox can develop shingles later in life (most commonly in the later years), as it’s caused by the same virus.

Shingles, or herpes zoster, is a painful condition. Alongside a painful rash and blisters, people often experience a burning, shooting pain, tingling, and/or itching.

The rash usually begins as a single stripe on one side of the body that turns into red blotches, before turning into blisters that scab over in 2–4 weeks.

Other symptoms can include:

  • headache
  • fever and chills
  • generally feeling unwell

Antiviral drugs and pain medications are often prescribed for people with shingles. Some at-home remedies include calamine lotion, wet compresses, and skin-soothing baths filled with oatmeal.

Scabies

Scabies is caused by an infestation of the skin by the human itch mite. The parasitic mites burrow into the upper layer of the skin where they live and lay eggs.

The most common symptoms of scabies are intense itching and a nonspecific itchy red scaly skin rash. Though the rash can develop on any part of the body, it can be commonly found on skin:

  • under the breast
  • around the nipples
  • between the fingers and toes
  • on wrists, palms, elbows, and armpits
  • on the waist or belt line
  • on the head, face, or neck
  • on soles of the feet in infants and children
  • in the groin area and buttocks

Scabies is highly contagious and can typically take 4 to 8 weeks to fully develop, but people can still spread the disease before exhibiting any symptoms.

FYI

There are no effective over-the-counter (OTC) medications for treating scabies. A doctor must prescribe medicated creams or lotions to kill the mites in order to alleviate symptoms.

It’s crucial to thoroughly decontaminate any bedding, clothing, towels, or fabric an infected person may have used within three days of treatment.

This may be done by:

  • washing in hot water
  • drying in a hot dryer
  • dry-cleaning
  • sealing items in a plastic bag for at least 72 hours.

Scabies mites generally don’t survive more than 2 to 3 days away from human skin.

Hives

Hives, or urticaria, is an itchy rash of red or skin-colored bumps and welts that can appear almost anywhere on the skin including under breasts.

Hives are often a result of an allergic reaction but the cause is usually not identified if the hives last less than six weeks. Triggers include:

  • medications, such as certain antibiotics, ibuprofen, and aspirin
  • foods, such as nuts, shellfish, and eggs
  • insect bites and stings
  • latex
  • animal dander (in the case of a severe allergy)
  • dust mites (in rare cases)
  • plants such as stinging nettle, poison oak, and poison ivy
  • emotional stress
  • physical triggers, such as pressure, temperature, sun exposure, and exercise
  • upper respiratory infection such as that due to a virus

Antihistamines are the best bet for treating hives. It’s key to see an allergist to find out your exact triggers so you can avoid them. For people with severe or persistent hives, a doctor may refer them to a dermatologist.

Contact dermatitis

Contact dermatitis is a type of eczema rash that occurs when the skin comes into contact with an irritant or has an allergic reaction to a substance.

It typically causes an itchy, red rash that may become swollen, dry, and blistered. These symptoms can take minutes, hours, or days to appear.

Common triggers of allergic contact dermatitis include:

  • soaps, shampoos, and permanent wave solutions
  • cosmetics, perfumes, and toiletries
  • jewelry
  • plants, such as poison ivy

Common triggers of irritant contact dermatitis include:

  • detergents, bleach, and disinfectants
  • chemicals and solvents
  • fertilizers and pesticides

Treatment of contact dermatitis depends on the cause, but can include:

  • emollients
  • topical and oral steroids

Cancer

Inflammatory breast cancer (IBC) is a very rare, very serious form of cancer in which the cancerous cells grow at a rapid rate.

Symptoms include:

  • pink, red, or purple skin discoloration
  • redness involving more than a third of the breast
  • pitted and/or thickening of the skin, often described as looking like an orange peel
  • one breast looking larger than the other because of swelling
  • one breast feeling warmer and heavier than the other
  • a breast that may be tender, painful, or itchy
  • a pimple-like rash across the breasts
  • an inverted or retracted nipple

Although this type of breast cancer is rare, it’s important to see your doctor immediately if you have these symptoms. IBC can be diagnosed with a biopsy and treated with a combination of chemotherapy, radiation, and surgery.

Seek medical attention if:

  • the rash becomes extremely painful
  • you see no improvement after home treatment for several days
  • you have open sores that won’t heal
  • you have a chronic condition or compromised immune system
  • you develop a fever, nausea, or vomiting
  • you develop multiple symptoms of any of the above conditions

  • Go braless as much as possible until the rash clears up. Especially avoid underwires. Wash bras frequently for when you do wear them.
  • Wear loose-fitting clothes made of fabrics that breathe, such as cotton and linen.
  • Use unscented soaps, lotions, and moisturizers.
  • Apply a cool compress to the area.
  • Use calamine lotion to help reduce itching.
  • Use drying powders such as Gold Bond Extra and Lady Anti Monkey Butt to help prevent rashes.
  • Stop using any new products that may have caused your rash.

Bottom line

Most of the time, a rash under or between your breasts — though objectively not the best part of your week — isn’t a cause for concern. With OTC oral and topical medications, and sometimes even simple home remedies, most go away on their own within a week or two.

However, if you have symptoms that could point to a more serious infection or potential breast cancer, see your doctor as soon as possible. It’s always better to be safe than sorry.

If the sweater stretchers are itchy, the lung protectors bumpy, the bazungas have blisters, the traffic stoppers have turned red (we could do this all day), it’s much more common than you think.

There are plenty of explanations that are both benign and immediately treatable by OTC medication. If you think your rash might be due to something more serious, be your breasts’ best friend and seek out a medical professional.