Boils and Carbuncles – Symptoms and Causes

Overview

What Is a Skin Boil

A skin boil, also called a furuncle, is a painful, pus-filled bump that develops under the skin. It happens when bacteria infect and inflame one or more hair follicles.

Boils typically begin as tender, reddish or purplish bumps. As they fill with pus, they grow larger and more painful until they eventually break open and drain. Boils commonly appear on the face, neck, armpits, thighs, and buttocks.

Most single boils can be treated at home. Remember not to squeeze or pierce a boil, as this can spread the infection to other areas of your body.

Understanding Carbuncles

A carbuncle forms when several boils cluster together, creating a larger, connected area of infection beneath the skin. This condition is more severe than a single boil and may cause a deeper infection.

Carbuncles often cause more significant pain and can take longer to heal than individual boils. They may also lead to fever and general feelings of illness.

Treatment options:

• Warm compresses: Apply to encourage boils to come to a head.
• Over-the-counter pain relievers: Help manage discomfort.
• Antibiotics: Prescribed for severe or recurring infections.
• Incision and drainage: An effective procedure for managing larger boils.

Seek medical help if a boil is very painful, lasts over two weeks, or is accompanied by a fever.

Signs to Watch For

Skin Bumps

Boils typically appear as painful, red bumps on the skin. They often start small but can grow larger than 2 inches across. These bumps usually form in areas with hair and sweat, such as the face, neck, armpits, thighs, and buttocks.

The skin around a boil often looks reddish or purple and swollen. As the boil grows over several days, it fills with pus. Eventually, a yellow-white tip forms at the center. This tip will break open, allowing the pus to drain out.

Clustered Infections

Carbuncles are significantly more severe than individual boils. They form when several boils cluster together, creating a connected area of infection under the skin.

People with carbuncles often experience:

• More severe pain
• Deeper skin infection
• Higher likelihood of scarring
• General feeling of illness
• Fever and chills

Carbuncles need more attention than single boils because they cover a larger area and can lead to more serious symptoms.

When to See a Doctor

Most small, single boils can be treated at home. However, medical attention is needed if you have multiple boils at once or if a boil:

• Appears on your face or affects your vision
• Gets worse quickly or causes severe pain
• Causes fever
• Grows larger despite home treatment
• Doesn’t heal within two weeks
• Comes back after healing

Causes

Boils typically result from a skin infection with Staphylococcus aureus bacteria. These bacteria normally live on skin surfaces and inside the nose without causing problems.

When bacteria enter through small breaks in the skin, such as cuts, scrapes, or insect bites, they can cause infection.

As the infection develops, white blood cells rush to the area, creating pus that collects under the skin. This forms the painful, red bump we call a boil.

Anything that damages your skin’s protective barrier increases your risk of developing boils.

Risk Factors

Several factors can increase your chance of developing boils or carbuncles:

• Living with someone who has a staph infection raises your risk through close contact.
• Diabetes weakens your body’s ability to fight skin infections.
• Existing skin problems, like acne or eczema, damage your skin’s protective barrier.
• Weakened immune systems make it harder for your body to fight bacterial skin infections.

Complications

Boils and carbuncles can sometimes lead to serious health problems. In rare cases, bacteria may enter the bloodstream, causing sepsis (blood poisoning). When this happens, the infection can spread to other body parts.

This spread might result in:

• Endocarditis – infection of the heart.
• Osteomyelitis – infection of the bone.

Prevention

Preventing boils isn’t always possible, especially for people with weakened immune systems. However, several practical steps can reduce your risk of developing staph infections.

Wash your hands frequently with mild soap or use alcohol-based hand sanitizers. Protect open wounds by keeping cuts and scrapes clean and covered with sterile, dry bandages until they heal completely.

Avoid sharing personal items with others, including towels, bedding, razors, clothing, and sports equipment. Staph bacteria can spread through shared objects and direct contact between people.

Wash your linens and towels in hot water with detergent and bleach, then dry them on high heat to kill bacteria if you have a cut or sore.