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What is cellulitis?

Cellulitis is a skin infection caused by bacteria. Normally, your skin helps protect you from infection. But if you have a cut, sore, or insect bite, bacteria can get into the skin and spread to deeper tissues. If it is not treated with antibiotics, the infection can spread to the blood or lymph nodes. This can be deadly.

Some people can get cellulitis without having a break in the skin. These include older adults and people who have diabetes or a weak immune system. These people are also more likely to develop dangerous problems from cellulitis. And they are more likely to get cellulitis again.

What causes cellulitis?

Cellulitis is caused by bacteria (usually strep or staph). Some people are at risk for infection by other types of bacteria. They include people with weak immune systems and those who handle fish, meat, poultry, or soil without using gloves.

What are the symptoms?

At first, the infected area will be warm, red, swollen, and tender. As the infection spreads, you may have a fever, chills, and swollen glands.

Cellulitis can occur anywhere on the body. In adults, it often occurs on the legs, face, or arms. In children, it is most common on the face or around the anus. An infection on the face could lead to a dangerous eye infection.

See a doctor right away if you have an infected area of skin and:

  • The infected area is getting redder, more painful, or larger, or it has red streaks extending from it.
  • You have a fever or chills.
  • The infected area is on your face or your groin.

How do you get cellulitis?

There are many ways to get cellulitis. You can get it if you have:

How is it treated?

Doctors use antibiotics to treat cellulitis. If the infection is mild, you may be able to take antibiotic pills at home. If the infection is severe, you may need to be treated in the hospital with antibiotics that go right into your bloodstream.

If your doctor prescribes antibiotics, it is important to take them as directed. Do not stop taking them just because you feel better. You need to take the full course of antibiotics.

It is very important to get treatment right away for cellulitis. If it is not treated, the bacteria can spread quickly through the body and cause sepsis, an extreme response by the body’s defense system. This can be deadly. Cellulitis on the face can spread to the brain and cause a dangerous infection (meningitis). Cellulitis can also cause other serious problems, such as blood clots in the legs (thrombophlebitis).

You are more likely to have these problems if you are an older adult, have a medical condition such as diabetes or peripheral arterial disease, or have a weak immune system. Your chances of the cellulitis coming back may be higher too.

How can you prevent cellulitis?

If you are at risk for cellulitis, you can take steps to help prevent it.

  • Take good care of your skin. Keep it clean, and use lotion to prevent drying and cracking.
  • Check your feet and legs often. This is especially important if you have diabetes.
  • Treat any skin infection, such as athlete’s foot, right away.
  • Ask your doctor if you need to take antibiotics on a regular basis to prevent cellulitis.
  • If your doctor prescribes medicine, take it just the way your doctor says to.

Frequently Asked Questions

Learning about cellulitis:

Being diagnosed:

Getting treatment:

Ongoing concerns:


Symptoms of cellulitis include tenderness, pain, swelling, and redness at the site of infection. If the infection spreads, you may have fever and chills, along with swollen lymph nodes. Sometimes, if cellulitis causes a high fever, you may have changes in mental function, such as confusion or sleepiness. Cellulitis can occur anywhere on the body, most often on the legs, face, or arms. Although the infection is not usually severe in adults, in some cases it can spread quickly, causing more intense symptoms.

Symptoms in infants and children

In children, cellulitis often affects the face, legs, arms, or the area around the anus. Swelling and redness are often widespread and lack distinct borders.

In infants, cellulitis can be serious because their immune systems cannot protect them from infection.

Symptoms in adults

In adults, cellulitis typically develops near a surgical site or at the site of an injury, such as a burn, a cut, or an animal bite. It usually affects the legs but can occur on other areas of the body, such as the face and ears. Pain and tenderness may be the first signs of cellulitis before visible signs of infection appear.

Cellulitis often comes back (recurs), especially if you have a weakened immune system or a condition that affects the health of your skin, such as a fungal infection or diabetes. Recurrence is also more common if you have problems with your blood circulation or with the lymphatic system, which drains fluids from your tissues. Recurring infection in the legs can cause a condition called elephantiasis, an enlargement of the skin on the legs and tissues in the legs.

Other conditions with similar symptoms (such as pain, swelling, and redness) include contact dermatitis and shingles.

Symptoms of cellulitis in the eye area

If cellulitis affects the eye area, you may have pain in and around the eye, restricted eye movement, and disturbances in your vision. Cellulitis affecting the eye requires urgent treatment to prevent permanent eye damage, blindness, or spread of the infection to the brain (meningitis).

Examinations and Tests

Doctors often diagnose cellulitis by looking at your symptoms. In most cases, you won't need further testing, and your doctor will prescribe antibiotics.

Sometimes ultrasound will be used to make sure there is not a blood clot in a deep vein. A CT scan or an MRI may also be done to rule out other problems.

If the initial treatment with antibiotics is not effective, your doctor may take samples of your blood and skin to identify the specific bacteria present so he or she can select a more effective antibiotic. Other lab tests usually are not helpful unless bacteremia (bacteria in the blood), sepsis, or another disease is suspected.

Treatment Overview

The intent of cellulitis treatment is to decrease the severity of the infection, speed up recovery, relieve pain and other symptoms, heal the skin, and prevent the infection from coming back.

Antibiotics are usually used to treat cellulitis. If the infection is limited to a small area, has not spread to the bloodstream or lymph system, and you don't have any other medical problems, antibiotics you take by mouth (oral) are effective. If the infection is more widespread, or if you're having a slow recovery on oral antibiotics, antibiotics may be used intravenously (IV) or by injection.

For cellulitis of the leg or arm, treatment also includes elevating the limb to reduce swelling.

Treatment for children depends on their age and which part of the body is infected. An antibiotic is usually given intravenously. Facial cellulitis in young children requires immediate treatment and responds well to antibiotics.1

Treatment sometimes requires a stay in the hospital. This is common if antibiotics must be given intravenously. But a hospital stay is also considered if you have signs of complications such as a high fever or if it will be hard for you to have follow-up care with a doctor.

Medicines used to treat cellulitis

Oral, topical (applied to the skin), or intravenous antibiotics may be used to treat cellulitis. The extent of the infection and its location help determine what type of antibiotic is used.

  • Oral antibiotics include penicillin, cephalexin, or cefaclor. For people who are allergic to penicillin, a cephalosporin or erythromycin can be used.
  • Topical antibiotics (antibiotics that you spread on the skin) may be used to treat mild cellulitis in some cases.
  • Intravenous (IV) antibiotics or antimicrobials may be used if the cellulitis is spreading quickly or you have a weakened immune system or a condition like diabetes.

Preventing a recurrence of cellulitis

Cellulitis tends to recur in people who have certain medical conditions that can lead to skin breakdown, such as edema (fluid buildup), fungal or bacterial infections, diabetes, or peripheral arterial disease.

  • If you have edema, support stockings and good skin hygiene may reduce or eliminate recurrence of cellulitis.2
  • If you have frequent fungal infections, regular use of antifungal medicines may help reduce recurrent cellulitis.
  • If you are considered very high risk for recurring cellulitis, taking preventive antibiotics may help.

Home Treatment

If you have cellulitis, follow your doctor's instructions about medicine and skin care. Other steps to help your recovery and keep cellulitis from coming back include the following:

  • Take all of your medicine as prescribed.
  • Take care of your skin. Any measure that prevents injury to your skin will help to prevent cellulitis. Use moisturizers to keep your skin from becoming dry and cracked.
  • Elevate your affected leg or arm to reduce swelling.
  • Apply warm compresses to the affected area.
  • Use pain relievers as needed.
  • Use support stockings to prevent fluid buildup.
  • Take steps to treat or prevent fungal infections, such as athlete's foot. If athlete's foot is hard to treat or recurs, ask your doctor about oral antifungal medicines. For more information on treating this condition, see the topic Athlete's Foot.
  • Take care of your feet, especially if you have diabetes or other conditions that may increase the risk of infection.
  • Avoid touching possible sources of infection, such as ill family members and their belongings; raw fish, meat, or poultry; or soil, particularly when you have an area of broken skin.

One study found that inflammation caused by toes rubbing together (toe-web intertrigo) may be a cause of cellulitis in the leg. This study showed that treating this skin inflammation could prevent cellulitis.3

When you have completed your course of medicine, follow up with your doctor to verify that the infection is gone.

Other Places To Get Help


Canadian Dermatology Association
1385 Bank Street
Suite 425
Ottawa, ON  K1H 8N4
Phone: 1-800-267-3376
(613) 738-1748
Fax: (613) 738-4695
Email: contact.cda@dermatology.ca
Web Address: www.dermatology.ca

The Canadian Dermatology Association promotes research and education for dermatologists, provides information and support for dermatology patients, and offers public education materials on sun awareness and skin care.



  1. Lin Y-TJ, Lu P-W (2006). Retrospective study of pediatric facial cellulitis of odontogenic origin. Pediatric Infectious Disease Journal, 25(4): 339–342.
  2. Pasternack MS, Swartz MN (2010). Cellulitis, necrotizing fasciitis, and subcutaneous tissue infections section of Skin and soft tissue infections. In GL Mandell et al., eds., Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 7th ed., vol. 1, pp. 1289–1312. Philadelphia: Churchill Livingstone Elsevier.
  3. Saavedra A, et al. (2008). Soft-tissue infections: Erysipelas, cellulitis, gangrenous cellulitis, and myonecrosis. In K Wolff et al., eds., Fitzpatrick's Dermatology in General Medicine, 7th ed., vol. 2, pp. 1720–1731. New York: McGraw-Hill Medical.

Other Works Consulted

  • Heagerty AHM (2010). Cellulitis and erysipelas. In MG Lebwohl et al., eds., Treatment of Skin Disease: Comprehensive Therapeutic Strategies, 3rd ed., pp. 132–134. Edinburgh: Saunders Elsevier.
  • Morris AD (2008). Cellulitis and erysipelas, search date May 2007. Online version of BMJ Clinical Evidence: http://www.clinicalevidence.com.
  • Saavedra A, et al. (2008). Soft-tissue infections: Erysipelas, cellulitis, gangrenous cellulitis, and myonecrosis. In K Wolff et al., eds., Fitzpatrick's Dermatology in General Medicine, 7th ed., vol. 2, pp. 1720–1731. New York: McGraw-Hill Medical.


By Healthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Primary Medical Reviewer Anne C. Poinier, MD - Internal Medicine
Specialist Medical Reviewer Alexander H. Murray, MD, FRCPC - Dermatology
Last Revised April 6, 2011

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