Cellulitis is a bacterial infection in the deeper layers of skin and the fat and soft tissue underneath. Symptoms can include skin discoloration, swelling, and tenderness. A person may require antibiotics for cellulitis.

There are around 14.5 million cases of cellulitis each year in the United States.

Some bacteria are naturally present on the skin and do not usually cause harm. However, if they enter the skin, an infection can result. Bacteria can enter the skin through cuts, grazes, or bites.

Cellulitis is not the same as cellulite, a harmless “orange peel” effect that can appear on the upper arms and thighs.

Cellulitis is a painful bacterial infection of the deeper layers of skin.

It can start suddenly and may become life threatening without prompt treatment.

Mild cases involve a localized infection, with redness in one area. More serious cases involve a rapidly spreading infection that can lead to sepsis.

The spread will depend, to some extent, on how strong the person’s immune system is.

There are different types of cellulitis, depending on where the infection occurs.

Some types include:

  • periorbital cellulitis, which develops around the eyes
  • facial cellulitis, which develops around the eyes, nose, and cheeks
  • breast cellulitis
  • perianal cellulitis, which develops around the anal orifice

Cellulitis can occur anywhere on the body, including the hands and feet. Adults tend to develop cellulitis in the lower leg, while children tend to develop it on the face or neck.

Cellulitis usually begins as a swollen, pink or red patch of skin that may increase in size and severity as the infection spreads.

The following symptoms may occur in the affected area:

  • discoloraiton and swelling
  • warmth
  • tenderness and pain

Some people develop blisters, skin dimpling, or spots.

A person may also experience other symptoms of an infection, such as:

  • fatigue
  • chills and cold sweats
  • shivering
  • fever
  • nausea

In addition, the lymph glands may swell and become tender. Cellulitis in the leg, for example, may affect the lymph glands in the groin.

Other similar conditions

There are several other conditions that share similar symptoms with cellulitis.

A few examples include:

  • Erysipelas: Similar to cellulitis, erysipelas is a bacterial skin infection characterized by redness and pain. However, erysipelas usually affects the outer layers of the skin, whereas cellulitis affects the deeper layers.
  • Stasis dermatitis: This condition occurs due to insufficient blood flow and typically affects the lower legs. It can cause skin discoloration, ulcers, and swelling, and may be treatable with lifestyle changes and medical or surgical procedures.
  • Dermatitis: Similar to cellulitis, dermatitis can cause skin discoloration, swelling, and blisters. However, it is usually the result of skin irritation and may be treatable with topical medications and antihistamines.
  • Deep vein thrombosis: This condition usually affects the legs and is the result of a blood clot in a deep vein. Though it also causes pain, swelling, and redness similar to cellulitis, its treatment usually involves taking a blood thinner such as warfarin.

Early treatment with antibiotics is usually successful. Most people receive treatment at home, but some need to receive it in a hospital.

A doctor may suggest one or more of the following treatments:

Medication

A mild case of cellulitis usually responds to oral antibiotic treatment in 7–14 days. The symptoms may initially worsen, but they usually start easing within 2 days.

Different types of antibiotics can treat cellulitis. The doctor will decide on the best option after taking into account the type of bacteria causing the infection and factors specific to each person.

Most people recover within 2 weeks, but it may take longer if the symptoms are severe.

A doctor may prescribe a low-dose oral antibiotic for a person to take long term to help prevent a reoccurrence.

Treatment in the hospital

Some people with severe cellulitis require hospital treatment, especially if:

  • they have a high fever
  • they are vomiting
  • they are experiencing a reoccurrence of cellulitis
  • the current treatment is not working
  • their symptoms are becoming more severe

In the hospital, most people with this type of infection receive antibiotic treatment through an IV, with a drip that delivers the medication through a vein in the arm.

Cellulitis is usually the result of bacteria from the Streptococcus and Staphylococcus groups.

These bacteria are common on the surface of the skin, where they are not harmful.

However, if they enter the skin, usually through a cut or scratch, they can cause an infection.

Cellulitis is not usually contagious but can be spread through contact if a person with an open wound touches skin that has an active infection.

Risk factors

Factors that can increase the risk of cellulitis include:

  • Age: Cellulitis is more likely to occur during or after middle age.
  • Obesity: Cellulitis is more common among people who have excess weight or obesity.
  • Leg issues: Swelling (edema) and ulceration can increase the risk of developing the infection.
  • Past cellulitis: Research suggests that anyone who has had cellulitis before has an 8–20% chance of it returning, and the infection can reoccur several times within a year.
  • Exposure to environmental factors: These include polluted water and some animals, including fish and reptiles.
  • Other skin issues: Chickenpox, eczema, athlete’s foot, abscesses, and other skin conditions can increase the risk of bacteria entering the body.
  • Lymphedema: This can lead to swollen skin that can crack and allow bacteria to enter.
  • Other conditions: People with liver or kidney disease have a higher risk of developing cellulitis.
  • Diabetes: If a person is not able to manage their diabetes effectively, problems with their immune system, circulation, or both can lead to skin ulcers.
  • Weakened immune system: People may have this if they are older, if they have HIV or AIDS, or if they are undergoing chemotherapy or radiotherapy.
  • Circulatory problems: People with poor blood circulation have a higher risk of infection spreading to deeper layers of the skin.
  • Recent surgery or injury: This increases the risk of infection.
  • IV drugs: Injecting drugs, especially with needles that they have used before, can lead to abscesses and infections under the skin, increasing the risk of cellulitis.

A doctor will examine the individual and assess their symptoms.

The doctor may ask about any medications a person is taking, their symptoms, and their medical history.

They may also collect a swab sample or take a biopsy to find out which type of bacteria is present. Laboratory tests can help rule out other possible causes, as other conditions can look similar to cellulitis.

Identifying the cause and type of bacteria enables a doctor to prescribe the most suitable treatment. However, this can be challenging, as the presence of various types of bacteria on the skin can lead to inaccurate results.

Questions that a person may want to ask their doctor include:

  • How long will treatment take?
  • What side effects may be caused by this medication?
  • How can infection be prevented in the future?
  • What are some ways to manage other preexisting medical conditions?

Serious complications can arise in rare cases. They include:

  • Permanent swelling: Without treatment, the person may develop permanent swelling in the affected area.
  • Blood infection and sepsis: This life threatening condition results from bacteria entering the bloodstream, and it requires rapid treatment. Symptoms of sepsis include a fever, a rapid heartbeat, rapid breathing, low blood pressure, dizziness when standing up, reduced urine flow, and skin that is sweaty, pale, and cold.
  • Infection in other regions: In very rare cases, bacteria that have caused cellulitis may spread and infect other parts of the body, including the muscles, bones, or heart valves. If this happens, the person needs immediate treatment.

In most cases, effective treatment can help prevent complications.

Cellulitis requires immediate medical treatment, meaning it will not respond to home treatment.

However, a person can do some things to feel more comfortable while waiting for medical attention and during treatment.

Tips include:

  • drinking plenty of water
  • keeping the affected area raised to help reduce swelling and pain
  • regularly moving the affected part of the body to help prevent stiffness
  • taking pain relief medication, such as ibuprofen
  • not wearing compression stockings until the infection has healed

Some people try natural remedies that have antibacterial properties, including thyme and cypress oil. However, there is not enough scientific evidence to show that any plant-based remedies can treat cellulitis.

Anyone with symptoms should receive medical help at once, because untreated cellulitis can be life threatening.

A person cannot always prevent cellulitis from developing, but there are some ways to reduce the risk.

Treat cuts and grazes: Keep any cut, bite, graze, or wound — including those from a recent surgery — clean to reduce the risk of infection.

Practice thorough hygiene: Wash hands often, shower regularly, and wear clean clothes to decrease the skin’s contact with bacteria.

Avoid scratching: If an insect bite, for example, is itchy, ask a pharmacist about how to reduce this feeling. When scratching is unavoidable, keeping the fingernails clean and short can help prevent infection.

Take care of the skin: Moisturizers can help prevent dry skin from cracking, but they will not help if an infection is already present.

Protect the skin: Wear gloves and long sleeves while gardening, and avoid wearing shorts if there is a likelihood of grazing the skin. Covering up can also help prevent insect bites.

Maintain a weight that is healthy for the individual: Having obesity may raise the risk of developing cellulitis.

Avoid smoking and limit alcohol consumption: These may also increase the risk of developing cellulitis.

Seek help for other medical conditions: Because people with certain health issues may be at a higher risk of infection, they should work with their doctor to help manage their condition.

Manage diabetes: Exercise regularly, take medications as prescribed, and limit consumption of processed foods and added sugar to maintain safe blood sugar levels and reduce the risk of infection.

People who take IV drugs can seek help through their doctor or by contacting the U.S. national helpline for treatment referral and information. The number to call is 1-800-662-HELP (4357). Calls are free and confidential and the line is open 24/7.

Cellulitis is a potentially severe infection in the deeper layers of the skin and the tissue beneath.

It can cause severe discomfort, and it can be life threatening. If a person seeks treatment as soon as symptoms appear, there is a good chance that the treatment will be effective.

Having cellulitis once increases the risk of it returning. However, a person can take steps to help prevent this.