What is cellulitis?
Cellulitis is a common skin infection that happens when bacteria spread through the skin to deeper tissues. Most cases are mild and last several days to a couple of weeks. But cellulitis can sometimes progress to a more serious infection, causing severe illness that affects the whole body (sepsis) or other dangerous problems.
Treatment is needed to help control the infection and reduce symptoms.
Some people are at higher risk for cellulitis, such as those who have diabetes, a weakened immune system, or edema. They also tend to get sicker from cellulitis. And they are more likely to get cellulitis again.
What causes cellulitis?
Cellulitis is caused by bacteria, most often strep or staph. You can get infected after any event that causes a break in the skin, such as:
- A cut or bite.
- A new tattoo or piercing.
- Problems that cause skin breakdown, such as eczema, psoriasis, or a fungal infection like athlete's foot.
Sometimes cellulitis can occur even if there wasn't an obvious break in the skin.
What are the symptoms?
At first, the infected area will be warm, red, swollen, and tender. If the infection spreads, you may have a fever, chills, and swollen lymph nodes.
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.
If you have signs of a skin infection, such as warmth, redness, swelling, or pain, see your doctor. Even minor infections may need to be treated.
How is it diagnosed?
Doctors are often able to diagnose cellulitis based on your symptoms and a physical exam. In most cases, you won't need further testing.
But tests sometimes may be done to find out what's causing your symptoms and to rule out other problems. For example, you may need blood tests, an ultrasound, or an imaging test such as a CT scan or an MRI.
How is it treated?
Cellulitis is treated with antibiotics. 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 a hospital so that you can get IV antibiotics directly into your bloodstream, along with any other care you may need.
Be sure to follow your doctor's instructions about medicine and skin care. To help with your recovery and to feel better:
- Take all of your medicine as prescribed. Don't stop taking it just because you feel better. You need to take the full course of antibiotics.
- Elevate the affected area to reduce swelling. Warm compresses may also help.
- Use pain relievers as needed.
Call your doctor if your symptoms get worse or if they haven't started to improve within 48 hours (2 days) after you start taking antibiotics.
How can you prevent cellulitis?
If you are at risk for cellulitis, you can take steps to help prevent it. If you've had cellulitis before, these steps may help prevent it from coming back.
- 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 right away.
- Ask your doctor if you need to take antibiotics or other medicine on a regular basis to prevent cellulitis.
- If you have edema, ask your doctor about wearing compression stockings or sleeves.
Other Works Consulted
- Habif TP (2010). Bacterial infections. In Clinical Dermatology, A Color Guide to Diagnosis and Therapy, 5th ed., pp. 335–381. Edinburgh: Mosby Elsevier.
- Habif TP, et al. (2011). Cellulitis. In Skin Disease: Diagnosis and Treatment, 3rd ed., pp. 160–163. Edinburgh: Saunders.
- 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.
- Lipworth AD, et al. (2012). Non-necrotizing infections of the dermis and subcutaneous fat: Cellulitis and erysipelas. In LA Goldman et al., eds., Fitzpatrick's Dermatology in General Medicine, 8th ed., vol. 2, pp. 2160–2169. New York: McGraw-Hill.
- Pasternack MS, Morton NS (2015). Cellulitis, necrotizing fasciitis, and subcutaneous tissue infections. In JE Bennett et al., eds., Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 8th ed., vol. 1, pp. 1194–1214. Philadelphia: Saunders.
Current as of: April 1, 2019
Author: Healthwise Staff
Medical Review: Martin J. Gabica, MD - Family Medicine
Adam Husney, MD - Family Medicine
E. Gregory Thompson, MD - Internal Medicine