How to Identify and Treat a Furuncle (Boil)

A furunclealso called a boil, is a bump on the skin filled with pus caused by an infection. It can resemble a large pimple, but furuncles are deeper in the skin and tend to be more painful.

The most common cause of furuncles is the Staphylococcus aureus (staph) bacteria, but other types of bacteria or fungi on the surface of the skin can also cause them. The infection grows into a hair follicle and the tissues under it.

Furuncles can go away on their own, but getting medical treatment is often a good idea to help relieve pain, prevent complications, and promote quicker healing.

What a Furuncle Looks Like

A boil can start as a swollen, tender, inflamed, pinkish-red area of the skin and then become a painful bump. The bump can feel like a cyst or water-filled balloon, filling with pus and dead tissue.

The boil is centered on a hair follicle.

Symptoms of a boil may include:

• Bump that ranges in size from a pea to a golf ball
• White or yellow center/head on the bump (forms after a few days)
• Oozing, weeping, or crusting
• Quick growth
• Spreading to other skin areas or joining with other boils

Symptoms that may accompany a boil include:

• Redness of the skin around the boil
• Itching before the boil develops
• Fever
• Fatigue
• Generally feeling ill

How to Get Rid of a Boil at Home Safely

For the boil to heal, the pus must escape, either on its own or when drained by a medical professional (never “pop” or drain a boil yourself; only healthcare providers should perform this task to avoid spreading infection). Occasionally, the boil may heal without draining, and the body reabsorbs the pus.

When the boil first appears and the pus-filled space hasn’t fully developed, applying a warm, moist compress can help bring the pus to the surface. This technique can help speed up the development of the abscess so that it can drain (or a healthcare provider) and heal.

Some ways to help a boil heal include:

• Wash your hands for 20 seconds before and after touching the boil.
• Wash the boil and keep it clean.
• Apply a warm, moist compress to the boil for about 10 minutes, three times a day.
• Use fresh towels every time you wash, dry, or otherwise touch the boil.
• If the boil bursts, cover it with a bandage.
• Change dressings and bandages often.
• Dispose of used dressings in a sealed bag to avoid infected fluid from coming into contact with anything else.
• Do not share or reuse items such as washcloths, clothing, towels, or bedding (wash items that have touched affected areas with hot water).
• Use antiseptic or antibacterial soap in your bath or shower daily for a week, then twice weekly for several weeks.
• Wash your hands regularly (use hand sanitizer if you can’t access a sink).
• If your healthcare provider recommends or prescribes medication (such as oral or topical antibiotics), follow directions carefully and finish the full course of treatment, even if your symptoms improve.

When to Contact a Healthcare Provider for Boils

Boils sometimes need treatment from a healthcare provider, including procedures to drain them or medications.

See a healthcare provider urgently if you have a boil and:

• It is on your face or spine.
• The skin around the boil feels hot, swollen, and painful.
• You have a weakened immune system (including from medication such as steroids or medical conditions such as diabetes).
• You feel hot and shivery.
• You have a fever and/or other symptoms (such as signs of infection like red streaks coming out of the sore, or a large buildup of fluid in the area).
• The boil is painful or causes discomfort.
• The boil lasts longer than one week.
• The boil returns.
• You keep getting boils (called furunculosis).

Systemic antibiotics may be recommended in situations such as:

• Boils that are bigger than 5 millimeters.
• Boils that don’t resolve with drainage.
• Fever.
• Signs of expanding cellulitis (serious skin infection).
• An immunocompromised or weakened immune system.
• People who are at risk of endocarditis (inflammation of the lining of the heart valves and chambers).

Possible Complications From Furuncles

Carbuncles

Carbuncles occur when several boils develop in nearby hair follicles and join together into a larger area of infection under the skin. They have multiple heads and typically go deeper into the tissue than boils do. Carbuncles often occur on the back of the neck.

Inflammation caused by a carbuncle may cause fever, weakness, and fatigue.

Spreading Infection

Infection can spread to other body areas, particularly if you squeeze or scratch it open. The bacteria can spread along the blood or lymph vessels. Red streaks leading away from the boil indicate lymphangitis (infection moving along a lymph vessel). Lymphadenitis (inflammation and pain in the lymph nodes in the affected area) can also occur.

A boil on the face (especially around the nose or upper lip area) carries a risk of bacteria entering the brain, which could lead to meningitis or cerebral venous sinus thrombosis (life-threatening blood clots in the large blood vessels).

Cellulitis (infection of the surrounding tissues) can also cause fever and illness.

Sepsis

Sepsis (the body’s extreme response to an infection) occurs when an infection triggers a life-threatening chain reaction throughout the body. Sepsis is a medical emergency.

Symptoms of sepsis may include:

• Clammy or sweaty skin
• Fever (including shivering or feeling cold)
• Confusion or disorientation
• High heart rate or weak pulse
• Extreme pain or discomfort
• Shortness of breath

MRSA

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of staph bacteria that can be resistant to certain antibiotics. An MRSA infection can cause boils.

Antibiotics taken for boils due to MRSA infection need to be a type that is effective against MRSA bacteria.

What Causes a Furuncle?

About 10% to 20% of people are staphylococcal carriers (they carry the bacteria Staphylococcus aureus on the surface of their skin), even if they are otherwise healthy and have good hygiene. This bacteria is commonly carried in the nostrils, between the legs, in the armpits, and in the cleft between the buttocks. It can move from the nostrils to other areas via fingernails.

Bacteria can enter the wall of a hair follicle and cause an infection in the follicle and surrounding tissue. The infection causes skin tissue inside the boil to die, creating an abscess (a pus-filled hollow space).

Factors that may increase the risk of developing a boil include:

• Weakened immune system
• Anemia
• Diabetes
• Smoking
• Iron deficiency
• Having chronic infections
• Cancer
• Eczema
• Conjunctivitis
• Certain allergies (such as allergic asthma)
• Having obesity
• Neutrophil defects
• Older age
• Hot and humid climates
• Blocked or abnormal follicular anatomy
• Poor hygiene
• Inadequate nutrition
• Broken skin (such as cuts or abrasions)

Can You Prevent Boils?

Measures that may help prevent boils include:

• Wash hands often.
• Keep nails trimmed.
• Clean and protect any skin injuries.
• Use clean razors, and don’t share them.
• Only bathe in hot tubs and spas that are well maintained.
• Avoid contact with others who have infections that can spread (if you have a boil, avoid swimming, gyms, and other places and activities where you may spread the infection).
• Bathe/shower regularly.
• Don’t share items such as towels.
• Practice healthy lifestyle habits, such as eating nutritious foods, exercising regularly, and avoiding smoking.
• Avoid picking your nose.
• Change your underwear and the clothes you sleep in regularly.
• Talk to your healthcare provider about your overall health.

If you have recurrent boils, your healthcare provider may suggest measures such as:

• Washing with antibacterial soaps or antiseptic washes
• Applying liquid soap containing either chlorhexidine gluconate with isopropyl alcohol or 2% to 3% chloroxylenol
• Addressing underlying risk factors
• Treating nasal carriage of S. aureus or MRSA colonization (if applicable)

Summary

Furuncles, also called boils, are caused by infections in the hair follicle, typically from staph bacteria.

Boils are painful, pus-filled bumps. They usually need to drain (either by bursting on their own or when drained by a healthcare professional) to heal. They should never be “popped” or drained at home.

Boils can heal independently or with home treatments such as warm, moist compresses, but seeing a healthcare provider can help them heal faster and reduce the pain. In some cases, medical treatment is necessary.