Cellulitis

Medically Reviewed by Poonam Sachdev on December 18, 2023
8 min read

Cellulitis is a common infection of the skin and the soft tissues underneath. It happens when bacteria enter a break in the skin and spread. The infection causes swelling, redness, pain, or warmth in the skin.

Most often cellulitis affects the lower legs. It can be in the face, arms, and other parts of the body, too. Cellulitis can be serious if bacteria get into the bloodstream.

Erysipelas vs. cellulitis

Erysipelas is another type of skin infection. Both erysipelas and cellulitis cause the same symptoms -- swollen, red, warm skin. The two conditions can be hard for even doctors to tell apart. One difference is that cellulitis affects deeper layers of skin than erysipelas.

Lymphedema and cellulitis

The lymphatic system is a network of vessels that's part of your immune system. These vessels carry a fluid called lymph that flushes bacteria out of your body to prevent infections.

Lymphedema is swelling under the skin caused by a buildup of lymph fluid. It happens when damage or a blockage in the lymphatic system prevents lymph fluid from draining.

You're more likely to get cellulitis if you have lymphedema. That's because a damaged lymph system can't protect you as well against infections.

Cellulitis happens when there's a break in the skin and bacteria get inside. It usually shows up on damaged skin such as inflamed wounds, dirty cuts, and areas with poor blood circulation.

Although many different types of bacteria cause cellulitis, the two most common types are Group A Streptococcus and Staphylococcus aureus. These bacteria live on your skin and underneath your fingernails.

Bacteria get into a cut or tear in the skin from:

  • An injury 
  • Surgery
  • A skin condition such as eczema, athlete's foot, or psoriasis
  • Foreign objects in the skin
  • Open wounds underneath the skin

Is cellulitis caused by poor hygiene?

Breaks in the skin are the most common cause of cellulitis, but it can happen in areas that aren't clean. To lower your risk, wash your hands with soap and water before you touch your skin. Shower regularly and put on clean clothes. And clean any wounds to prevent bacteria from getting inside.

Is cellulitis contagious?

Cellulitis isn't contagious. Usually, it doesn't pass from one person to another. The only way it might spread this way is if one person has an open wound that directly touches another person's open wound.

Common parts of the body affected by cellulitis are your legs, feet, and toes, as well as your arms, hands, and fingers. Doctors also label types of cellulitis based on where the infection starts, including:

Periorbital cellulitis

This is an infection of the eyelid or the skin around the eye. It's most common in children. The cause is often an injury or sinus infection. Periorbital cellulitis usually isn't serious. Most children with this infection get better after they take antibiotics for about a week.

Orbital cellulitis

Orbital cellulitis is less common than the periorbital type, but it can be more serious. Like periorbital cellulitis, it starts when bacteria spread from an injury or sinus infection into the eye. But in this case, the bacteria get deeper into the fat and muscles of the eye. Orbital cellulitis can cause blindness without treatment.

Perianal cellulitis

This infection mainly affects children under 10. It starts in the perineum, the area between the anus and the scrotum in boys, or between the anus and vulva in girls. Strep bacteria most often cause perianal cellulitis.

Facial cellulitis

Cellulitis can affect the face, although a skin infection on the face is more likely to be from erysipelas. Facial cellulitis happens when bacteria spread to the face from a(n):

  • Ear infection
  • Gum infection
  • Injury
  • Insect bite
  • Sinus infection

Breast cellulitis

Breast cellulitis is an infection of the breast. It happens when bacteria build up in the sweat underneath the breasts. The skin of the breast becomes red, warm, and swollen. Some people also have flu-like symptoms such as a fever and chills.

You're more likely to get breast cellulitis if you:

  • Are overweight
  • Have large breasts
  • Had surgery or radiation therapy to treat breast cancer

Cellulitis in the breast can spread quickly if you don't treat it.

Cellulitis from a bug bite

Insects don't transmit the bacteria that cause cellulitis through their bites or stings. However, the break in your skin from a bite or sting gives the bacteria a way to enter your body and cause an infection. The bacteria that cause cellulitis live on your skin and in your nose and mouth, even if you're healthy. 

Cellulitis symptoms usually start with a small area of skin that's red, swollen, tender, and warm. The skin may be pitted like an orange peel or develop blisters. You may have a fever and chills.

Other common symptoms include:

  • A sore or rash that grows quickly
  • Warmth
  • Pain or tenderness
  • Tiredness
  • Yellow, clear fluid or pus leaking from the area

Get medical help for any of these more serious symptoms:

  • High fever (100.4 F or higher) 
  • Nausea and vomiting
  • Shaking chills (rigors)
  • Growing or hardening of the reddened area
  • Increased pain
  • Numbness when you touch the area
  • Dizziness
  • Confusion

You’re more likely to get cellulitis if you:

  • Have an injury to the skin
  • Have a weak immune system from diabetes, cancer such as leukemia, or HIV/AIDS
  • Have circulatory problems, such as insufficient blood flow to your arms and legs, poor drainage of your veins or lymphatic system (lymphedema), or varicose veins -- twisted, enlarged veins near the surface of the skin
  • Had chickenpox or shingles
  • Had cellulitis in the past
  • Have a skin condition such as eczemapsoriasis, or athlete's foot
  • Have liver disease such as chronic hepatitis or cirrhosis
  • Are overweight
  • Had a coronary artery bypass graft procedure

Often doctors can diagnose cellulitis based on how the skin looks. Your doctor will ask about your symptoms and examine your skin. You might need a blood test to rule out other conditions with similar symptoms. Other procedures could include:

  • An X-ray. This is used to see if there’s a foreign object in your skin or if the bone underneath is possibly infected.
  • A bacterial culture. Your doctor will use a needle to remove fluid from the area and send it to the lab.

Rarely, the infection can spread and cause complications such as:

  • Bacteremia, a blood infection
  • Endocarditis, an infection of the inner linings of the heart's valves and chambers
  • Osteomyelitis, a bone infection
  • Sepsis, an extreme whole-body response to infection
  • Toxic shock syndrome, a life-threatening condition caused by bacterial toxins
  • Suppurative arthritis, an infection in a joint
  • Necrotizing fasciitis, an infection that destroys tissue under the skin

Get medical help right away if you have cellulitis along with any of the following symptoms:

  • A large area of skin that's red and inflamed
  • Numbness, tingling, or other changes in the affected area
  • Skin that has turned black
  • A red and swollen area around your eyes or behind your ears

While treating cellulitis, the goal is to get rid of the bacteria that caused the infection. Usually, the way to do that is with antibiotics.

Cellulitis antibiotics

Cellulitis treatment usually includes an antibiotic such as dicloxacillin or cephalexin, which you take by mouth for 5-10 days. Which antibiotic you need will depend on what type of bacteria caused your cellulitis.

Take the full course of antibiotics, even if you feel better. You may need to take antibiotics for 7-14 days or longer if you have a weakened immune system. Some people need more than one type of antibiotic.

You may get treatment in a hospital if:

  • Cellulitis doesn't get better after a few days of taking antibiotic pills
  • It covers a large area of your body
  • You have a weak immune system
  • The infection is around your eyes

The hospital can give you antibiotics right into one of your veins (IV treatment). You may need to stay in the hospital for a few days if you have a serious case of cellulitis.

Cellulitis home remedies

Take care of your wound. Keep it covered to help it heal faster. Your doctor will let you know if you need to put special dressings or medicines on the infected area.

Here are some other ways to manage cellulitis at home:

  • Prop up the part of your body with cellulitis. This will relieve swelling and help the infection heal.
  • Hold a warm compress to your skin in the affected area.
  • Wear a compression wrap or stocking to bring down swelling and improve blood flow.
  • Ask your doctor if you can take an over-the-counter nonsteroidal anti-inflammatory drug (NSAID) pain reliever such as ibuprofen (Advil, Motrin), aspirin, or naproxen (Aleve) to keep you comfortable.

Most of the time, antibiotics are enough to treat cellulitis. Surgery usually isn't necessary, unless your doctor needs to open and drain an abscess or remove pus that has collected in the tissue. They may also cut away dead tissue to help the area heal.

Use these tips to avoid cellulitis:

  • Practice good personal hygiene, and keep your skin clean.
  • Rub a lotion or moisturizer onto your skin to prevent cracks.
  • Wear sturdy, well-fitting shoes or slippers with loose-fitting cotton socks. Don’t walk barefoot outdoors.
  • Keep wounds clean. Wash the wound every day with soap and water and cover it with a fresh, clean bandage. Watch for signs of infection such as redness and pus.
  • Trim your nails carefully to avoid injury.
  • If you have diabetes, check your feet every day for sores you might not feel. Quickly treat any injuries or infections.
  • Manage conditions that can cause cellulitis, such as eczema, athlete's foot, and lymphedema.
  • To prevent insect bites, use an insect repellent approved by the Environmental Protection Agency (EPA). Wear a long-sleeved shirt and pants when you go outside in areas where there are biting insects.
  • Clean insect bites with soap and water. Apply an antibiotic ointment if the skin is broken. Cover the bite with a bandage to keep it clean and prevent you from scratching.

Some injuries are more likely to cause cellulitis than others. See your doctor if you have:

  • Animal or human bites
  • Puncture wounds deeper than a half-inch, such as from stepping on a nail
  • Crushed tissue that bleeds
  • Burns that blister
  • Frostbite
  • Deep injuries with dirt in them
  • Injuries that touch seawater (making them more prone to infection), especially if you have liver disease
  • Diabetes or other major medical conditions, such as liver or kidney disease
  • Swelling in your arms and legs that does not go away

Cellulitis should go away after you take antibiotics for 7-10 days. You may need to take antibiotics for longer if the infection is serious.

In rare cases, cellulitis can spread through the bloodstream and cause more serious problems, such as a heart infection or blood infection. You may need treatment in a hospital if that happens.