Cellulitis is a common and sometimes painful bacterial skin infection. It may first appear as a red, swollen area that feels hot and tender to the touch. The redness and swelling can spread quickly.

It most often affects the skin of the lower legs, although the infection can occur anywhere on your body or face. Cellulitis is usually on the surface of your skin, but it may also affect the tissues underneath. The infection can spread to your lymph nodes and bloodstream.

If you don’t treat cellulitis, it could become life-threatening. Get medical help right away if you have symptoms.

Cellulitis symptoms include:

  • pain and tenderness in the affected area
  • redness or inflammation of your skin
  • a skin sore or rash that grows quickly
  • tight, glossy, swollen skin
  • a feeling of warmth in the affected area
  • an abscess with pus
  • fever

More serious cellulitis symptoms include:

Symptoms like these could mean that cellulitis is spreading:

Contact your doctor right away if you have any of these symptoms.

Cellulitis treatment involves taking antibiotics by mouth for 5 to 14 days. Your doctor may also prescribe pain relievers.

Rest until your symptoms improve. Raise the affected limb higher than your heart to reduce swelling.

Cellulitis should go away within 7 to 10 days after you start taking antibiotics. You might need longer treatment if your infection is severe due to a chronic condition or a weakened immune system.

Even if your symptoms improve within a few days, take all the antibiotics your doctor prescribed. This will make sure all of the bacteria are gone.

Contact your doctor if:

  • you don’t feel better within three days after starting antibiotics
  • your symptoms get worse
  • you develop a fever

You may need to be treated with IV antibiotics in a hospital if you have:

  • a high temperature
  • low blood pressure
  • an infection that doesn’t improve with antibiotics
  • a weakened immune system due to other diseases

Cellulitis occurs when certain types of bacteria enter the skin through a cut or crack. Staphylococcus and Streptococcus bacteria can cause this infection.

The infection can start in skin injuries such as:

  • cuts
  • bug bites
  • surgical wounds

Your doctor will likely be able to diagnose cellulitis just by looking at your skin. A physical exam might reveal:

  • swelling of the skin
  • redness and warmth of the affected area
  • swollen glands

Depending on the severity of your symptoms, your doctor may want to monitor the affected area for a few days to see if the redness or swelling spread. In some cases, your doctor may take blood or a sample of the wound to test for bacteria.

Cellulitis usually doesn’t spread from person to person. Yet it’s possible to catch cellulitis if you have an open cut on your skin that touches an infected person’s skin.

You’re more likely to catch cellulitis if you have a skin condition like eczema or athlete’s foot. Bacteria can enter your skin through cracks that these conditions cause.

A weakened immune system also increases your risk of catching cellulitis because it can’t protect you as well against the infection.

If you do catch cellulitis, it could be dangerous if you don’t get treated. That’s why it’s important to tell your doctor.

Cellulitis is treated with antibiotics you get from your doctor. Without treatment, it can spread and cause a life-threatening infection.

But there are things you can do at home to relieve pain and other symptoms.

Clean your skin in the area where you have cellulitis. Ask your doctor how to properly clean and cover your wound.

If your leg is affected, raise it above the level of your heart. This will help reduce swelling and relieve pain.

Here’s how to take good care of your skin at home while you recover from cellulitis.

Antibiotics generally clear up the infection in most people. If you have an abscess, it may need to be drained with surgery.

You first get medicine to numb the area. Then the surgeon makes a small cut in the abscess and allows the pus to drain out.

The surgeon then covers the wound with a dressing so it can heal. You may have a small scar afterward.

Several factors increase your risk for cellulitis, including:

  • a cut, scrape, or other injury to the skin
  • a weakened immune system
  • skin conditions that cause breaks in the skin, such as eczema and athlete’s foot
  • intravenous (IV) drug use
  • diabetes
  • a history of cellulitis
  • swelling of your arms or legs (lymphedema)
  • obesity

If you have a break in your skin, clean it right away and apply antibiotic ointment. Cover your wound with a bandage. Change the bandage daily until a scab forms.

Watch your wounds for redness, drainage, or pain. These could be signs of an infection.

Take these precautions if you have poor circulation or a condition that puts you at risk for cellulitis:

  • Keep your skin moist to prevent cracking.
  • Promptly treat conditions that cause cracks in the skin, like athlete’s foot.
  • Wear protective equipment when you work or play sports.
  • Inspect your feet daily for signs of injury or infection.

Your symptoms may get worse in the first day or two. They should begin to improve within one to three days after you start taking antibiotics.

Finish the whole dose your doctor prescribed, even if you feel better. This will ensure that all the bacteria are gone.

During your recovery, keep the wound clean. Follow your doctor’s recommendations for washing and covering the affected area of skin.

Most people fully recover from cellulitis after 7 to 10 days on antibiotics. It’s possible for the infection to come back in the future.

If you’re at high risk, your doctor may put you on a longer dose of antibiotics. This will help prevent you from getting cellulitis again.

You can prevent this infection by keeping your skin clean if you get a cut or other open wound. Ask your doctor if you’re unsure how to properly care for your skin after an injury.

Erysipelas is another skin infection caused by bacteria, most often group A Streptococcus. Like cellulitis, it starts from an open wound, burn, or surgical cut.

Most of the time, the infection is on the legs. Less often, it can appear on the face, arms, or trunk.

The difference between cellulitis and erysipelas is that the cellulitis rash has a raised border that makes it stand out from the skin around it. It may also feel hot to the touch.

Other symptoms include:

  • fever
  • headache
  • nausea
  • chills
  • weakness
  • ill feeling

Doctors treat erysipelas with antibiotics, most often penicillin or a similar drug.

High blood sugar from uncontrolled diabetes can weaken your immune system and leave you more vulnerable to infections like cellulitis. Poor blood flow in your legs also increases the risk.

People with diabetes are more likely to get sores on their legs and feet. The bacteria that cause cellulitis can enter through these sores and cause infection.

If you have diabetes, keep your feet clean. Use a moisturizer to prevent cracks. And check your feet every day for signs of infection.

An abscess is a swollen pocket of pus underneath the skin. It forms when bacteria — often Staphylococcus — get into your body through a cut or other open wound.

Your immune system sends in white blood cells to fight off the bacteria. The attack can form a hole under your skin, which fills with pus. The pus is made up of dead tissue, bacteria, and white blood cells.

Unlike cellulitis, an abscess looks like a lump under the skin. You may also have symptoms like a fever and chills.

Some abscesses shrink on their own without treatment. Others need to be treated with antibiotics or drained.

Dermatitis is a general term for a swollen skin rash. It’s caused by an infection or an allergic reaction, usually not by bacteria.

Contact dermatitis is an allergic reaction to an irritating substance. Atopic dermatitis is another term for eczema.

Symptoms of dermatitis include:

  • red skin
  • blisters that ooze or crust
  • itching
  • swelling
  • scaling

Doctors treat dermatitis with cortisone creams and antihistamines to relieve the swelling and itching. You will also need to avoid the substance that caused the reaction.

Deep vein thrombosis (DVT) is a blood clot in one of the deep veins, usually in the legs. You can get a DVT after you sit or lie in bed for a long period of time, such as on a long plane trip or after surgery.

Symptoms of DVT include:

  • pain in the leg
  • redness
  • warmth

It’s important to get medical help if you have DVT. If the clot breaks free and travels to the lungs, it can cause a life-threatening condition called pulmonary embolism (PE).

Doctors treat DVT with blood thinners. These medicines prevent the clot from getting bigger and stop you from getting new clots.