Boils are skin infections — usually bacterial — that start deep inside the skin and often involve hair follicles. Another name for a boil is a furuncle. Boils usually look like red bumps or lumps on the skin, and over time they fill with pus. They often occur on the buttocks.

The most common symptom of a boil is having a red, tender, and painful bump or lump on the skin. You may also see red skin and swelling around the bump.

A boil usually begins as a painful or tender spot on the skin and tends to be small, or about the size of a pea. It usually becomes firm or hard.

The bump can continue to grow and can fill with pus. At this stage, it tends to be softer and larger.

Eventually, a yellow or white tip and can rupture with pus leakage. Some boils don’t rupture and may end up with a crust that forms on top of the bump. A boil can also ooze clear liquid.

Boils can be big and reach the size of a golf ball.

Several skin conditions can resemble boils. They include cystic acne, infected sebaceous cysts, and other skin infections.

Bacterial infections are the most common cause of boils on the buttocks. Staphylococcus aureus is usually the bacterium responsible for the boils. This bacterium often lives on the skin or inside the nose.

Skin folds are a common site for boils. Areas of the body that have hair, sweat, and friction are more likely to have boils.

Common risk factors for boils include:

  • being a Staphylococcus aureus carrier, which means chronically having this bacterium on the skin
  • having eczema
  • having close contact with or living with someone who has boils
  • having diabetes mellitus
  • having a condition that reduces your immune system function
  • having anemia from iron deficiency
  • having small cuts or injuries to the skin
  • tobacco smoking

Diagnosis of a boil on the buttocks includes a medical history and physical exam. Your doctor may also order blood tests or take a sample of the pus to determine the cause of the infection.

There are many treatment options available for boils. However, it’s important to avoid popping or puncturing the boil yourself. The infection can spread to other parts of the body and lead to complications.

Home remedies

Home remedies for addressing boils include:

Oral and topical medications

Oral and topical medications for preventing boils from occurring or spreading include:

Lifestyle changes

Lifestyle changes include:

  • not picking at the boil or other sores
  • washing your clothes and towels separately to avoid spreading the infection
  • changing sheets daily and washing them
  • bathing regularly
  • keeping the home clean
  • losing weight to reduce skin folds
  • avoiding gyms, swimming pools, and contact sports while your boils are healing, so any infection doesn’t spread to others
  • avoiding tobacco smoking
  • eating a healthy diet

Medical procedures

In some cases, large boils that don’t go away on their own require medical intervention. Medical procedures for boils include:

  • making an incision (lancing) and draining the boil
  • packing an incision with gauze to collect the pus and help allow the skin to heal properly

It’s possible to have complications from a boil on the buttocks. Usually, they’re caused by the infection spreading to other parts of the body. Complications may include:

  • severe scarring
  • a cluster of connected boils (carbuncle)
  • sepsis (severe infectious inflammation)
  • cellulitis, which is inflammation of the skin and adjacent soft tissue
  • endocarditis, which is inflammation of the heart
  • osteomyelitis, which is inflammation of the bone

Boils are contagious and can spread to other people. You can also spread them to other parts of your own body. However, you can take several steps to prevent boils:

  • Avoid close skin contact with people who have boils or who are Staphylococcus aureus carriers.
  • Wash your hands throughout the day.
  • Bathe regularly.
  • Wash all clothes, towels, and other personal items after having a boil.
  • Avoid sharing towels and other personal items with other people.
  • Protect and cover all open skin injuries or wounds.

You may be able to make a complete recovery from a boil on the buttocks with just supportive home therapies. Larger boils may require a visit to a physician for a treatment plan. A large or deep boil may leave behind a red mark or scar on the skin as it heals. However, in some cases, a skin infection and boils can come back.

Boils are skin infections that appear as red, painful bumps, which eventually swell and fill with pus. They commonly appear on the buttocks and in skin folds where sweat collects. The most common cause of boils on the buttocks is a bacterial infection. Large boils may require a visit to the doctor.

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