Cellulitis: How Long Does It Take To Heal The Legs?

Cellulitis is an infection of the deeper layers of the skin. It develops when bacteria enter through a cut, bite, or wound — including small cuts in cracked, dry skin. Common bacteria that live on the skin, Staphylococcus or Streptococcus, are the common causes. Although cellulitis can occur anywhere on the body, the most common location is the lower leg.

Arash Mostaghimi, a dermatologist at Brigham and Women’s Hospital and associate professor of medicine at Harvard Medical School, weighs in on new research that addresses important questions about how long it takes to heal completely.

What are the symptoms of cellulitis?

The body’s natural immune response to this bacterial invasion causes a painful rash that appears red on lighter skin and dark purple on darker skin. The affected area may also be swollen and feel hot.

How is cellulitis treated?

The usual treatment is five to 10 days of antibiotic pills. More severe cases may require intravenous antibiotics.

How quickly do antibiotics help resolve cellulitis?

After starting antibiotic treatment, people usually notice improvement within a few days. However, the area may remain swollen, hot, and painful even after 10 days.

Does that mean antibiotic treatment is ineffective? Not necessarily, according to a recent study of people with lower leg cellulitis that describes the natural history of recovery stages after antibiotics.

“The healing process has two parts, so a full recovery takes longer than you think,” said Dr. Mostaghimi.

First, the antibiotics and your white blood cells work together to kill the bacteria. But your body’s resistance against bacteria can take a long time to shut down. As a result, this second stage of the healing process may include some residual symptoms, he explained.

What did the study find?

The study included 247 people with mild to moderate cellulitis on the lower leg who received antibiotics for seven to 10 days. On the 10th day:

• Their swelling decreased by 50%, and the size of the affected area decreased by about 55%.
• A blood marker of inflammation, C-reactive protein, fell during treatment and reached near-normal levels in all participants.
• However, more than half continued to report discomfort in the affected leg, with 14% ranking their pain as 5 or more on a scale of 1 to 10.

This pattern of discomfort is not unusual, especially for leg infections, said Dr. Mostaghimi. While people are recovering from leg cellulitis, they are often advised to elevate the leg, which helps to relieve the swelling. (Putting a warm, wet washcloth on the area may also help.)

But after they feel better and start walking more, the fluid returns to the legs. So it’s not surprising that the area may feel a little swollen and uncomfortable again once they get back up, she says.

Who is most at risk of cellulitis?

Remember, cellulitis usually occurs when bacteria that normally reside on our skin are able to breach that shield to enter the body.

Some people who develop cellulitis have no obvious injury or damage to the skin to explain the infection, which can occur in people who are generally healthy. However, people with certain health problems are more prone to cellulitis. This includes people who are overweight or have diabetes, a weak immune system, poor circulation, or chronic edema (swollen limbs).

In addition, skin conditions such as eczema and athlete’s foot can create small cracks in the skin that make it easier for bacteria to penetrate deeper into the skin, Dr. Mostaghimi said. Scratching the bug bite until it bleeds is another possible introduction of bacteria.

What happens if cellulitis is not treated?

Untreated cellulitis can be very serious. The rash may spread, be surrounded by blisters, and become more painful. Nearby lymph nodes may become tender and swollen, followed by fever and chills. Seek medical attention immediately if you experience these symptoms.

The bottom line

“It’s important for people with leg cellulitis to realize that it may take a while after you finish your antibiotics to fully resolve all of your symptoms,” says Dr. Mostaghimi. You may feel better within a few days, but always finish all your prescription antibiotic pills. However, having residual symptoms when you’re done doesn’t mean you need another course of antibiotics or a different antibiotic, he says.