Rash on Breast: Stress, Hormones, or Something Else?

A rash on the breast is most often caused by heat or moisture—in rare cases, it could be caused by infection or cancer

Medically reviewed by Renita White, MD

Having a rash on your breast can be uncomfortable and embarrassing. There are lots of possible reasons for a rash on the breast, and different areas, such as an underboob rash, rash on the nipple, redness around the nipple, or rash on the side of the breast, can point to different causes. When you know what might be causing your rash, you can find treatment and see a healthcare provider.

Continue reading to learn more about a rash on the breast (in males and females), including possible causes, treatments, and when to seek help.

Noncancerous Causes of Rash on Breast

The most common causes of a rash on the breast have nothing to do with cancer. Still, they can be very uncomfortable. Here are a few common causes of a rash on the breasts and under the breasts.


The most common cause of a rash on the breast or an underboob rash is intertrigo. It’s an itchy red rash that happens in the folds of skin, including under the breasts. It happens when yeast, other fungi, or bacteria grow in warm, moist skin folds. The symptoms include:

  • An intensely red rash

  • Burning, itching, or stinging

  • Raw, glistening skin

You can prevent intertrigo by wearing a bra or liner to stop your breasts from rubbing on the skin of your abdomen. If you have the rash, try treating it with a barrier cream, like Vaseline or Desitin. For more severe intertrigo, see your healthcare provider. They may suggest an antibacterial or antifungal cream.

Heat Rash

Another cause of underboob rash is heat rash, which happens when sweat glands become blocked, trapping sweat under the skin. The symptoms include:

  • Small bumps with a red spot surrounding them

  • Itchiness

  • Prickling sensation

Heat rash usually resolves on its own. Cool compresses and avoiding excess heat can help.


Breast eczema can cause a rash on or around the nipples, areola, or other areas of the breast. Symptoms of breast eczema include:

  • Red, itchy, painful skin

  • A rash that’s warm to the touch

  • Dry, crusted skin

  • Pus or oozing

Treatment for breast eczema includes a skin care routine, avoiding triggers like fragrances, and working with a dermatologist.

Allergic Reactions

Allergic reactions can cause a breast rash that includes hives. The symptoms of an allergic rash will likely include:

  • Welts with a clearly defined border

  • Red, itchy skin

  • A rash that turns white (blanches) when pressed

Hives usually resolve on their own, but if you have any serious symptoms including changes in your breathing, see a healthcare provider immediately.


Infections including shingles and scabies can cause breast rashes. Symptoms vary depending on the root cause, but may include:

  • A rash on only one side of the body

  • Pimple-like appearance

  • Intensely itchy or painful rash

If you believe you have shingles, scabies, or another type of infection, see your healthcare provider.

Mastitis is an infection that occurs in people who are lactating when a milk duct becomes clogged, then infected. It may cause a rash, redness, or swelling on the breast, along with flu-like symptoms.


Pregnancy and the hormonal changes that accompany it can cause pregnancy-related rashes on the breasts. Pruritic urticarial papules and plaques of pregnancy (PUPPP) is one of the most common pregnancy rashes. Symptoms of PUPPP start on the abdomen and can spread, including to the breasts. Symptoms include:

  • Small itchy bumps that may look like hives

  • Raised plaques, or areas of bumps

  • Intense itchiness

Cancerous Causes of Rash on Breast

Although cancer is rarely the cause of a breast rash, the idea of cancer can be really scary. So, it’s important to be aware that in rare cases, a breast rash can be a sign of cancer, sometimes appearing before or instead of a lump. Here are two cancerous causes of a rash on the breasts.

Inflammatory Breast Cancer

Inflammatory breast cancer is a rare but aggressive form of breast cancer that can occur in males or females. The first sign of this cancer is often a rash that appears suddenly. The appearance of the rash can vary, but symptoms include:

  • Swelling in the breast

  • Discoloration, which might appear red, purple, or another color

  • Sudden changes to the breast size, color, or texture

  • Nipple retraction

  • Itchiness and warmth on the breast

If you experience these sudden changes, you should see your healthcare provider immediately.

Paget’s Disease of the Breast

Another cancerous cause of a breast rash, including redness on the nipple or a rash on the nipple, is Paget’s disease of the breast (or nipple). This is a rare type of cancer in the nipple or areola. Symptoms may come and go but often appear only on one breast. They include:

  • Itchy, burning sensation around the nipple

  • Flaking, crusting, or thick skin around the nipple

  • Flattened nipples

  • Discharge from the nipple

  • Pain

If you experience these symptoms, see a healthcare provider right away.

Complications and Risk Factors

In most cases, a rash on the breasts is not particularly serious. However, because there are so many different causes of breast rash, serious causes can be misdiagnosed or mistreated. For example, inflammatory breast cancer might be mistaken for mastitis, or Paget’s disease might be mistaken for eczema. Follow your healthcare provider’s advice but continue to advocate for yourself if treatment doesn’t resolve your symptoms.

Tests and Exams to Diagnose Breast Rash

Oftentimes, a healthcare provider can diagnose the cause of your breast rash through a physical exam. In addition, they may order:

How to Manage Rash on Breast at Home

Keeping your breasts dry can help prevent many rashes. Wearing a bra, liner, or barrier cream to keep your breasts from rubbing may help. In addition, avoid any triggers or allergens, which can include certain fabrics, scented soaps, and detergents.

When to Visit a Healthcare Provider

See a healthcare provider whenever you notice sudden changes in your breasts, including swelling, discoloration, or discharge. When coupled with a breast rash, these can be signs of serious infection or—in rare cases—cancer.


There are many possible causes of breast rash, most of which are relatively harmless (though uncomfortable). Keeping your breasts dry and cool can help prevent heat rash and intertrigo, two of the most common causes of breast rash. In very rare cases, a breast rash can be a sign of cancer. If you notice sudden changes in your breast size, color, or texture—especially if those changes are only on one side—see a healthcare provider immediately.

Read the original article on Verywell Health.