Angular cheilitis, also known as angular stomatitis and perlèche, causes swollen red patches in the corners on the outside of your lips.

It can occur on one or both sides of your mouth. It’s an inflammatory condition and can last a few days or be a chronic problem. It can affect people of all ages, including infants.

Symptoms of angular cheilitis will almost exclusively appear at the corners of the mouth. The symptoms can be both painful and frustrating. Symptoms can vary from having only mild redness to having open, bleeding blisters.

If you’re experiencing angular cheilitis, the corners of your mouth may be:

  • bleeding
  • red
  • swollen
  • cracked
  • blistered
  • crusty
  • itchy
  • scaly
  • painful

Other symptoms include:

  • bad taste in your mouth
  • burning feeling on your lips or mouth
  • lips feeling dry or chapped
  • difficulty eating as a result of the irritation

There are several different causes of angular cheilitis. The most common is yeast infection as a result of saliva.

Saliva can build up and get trapped in the corners of the lips, which causes lips to crack. A person may lick their lips more in an attempt to soothe the pain or dryness of their lips. This excess saliva will sit in the corners, which is the perfect warm environment for fungus like yeast to grow.

Viruses and bacteria can also cause it to develop.

Certain people are more at risk for developing angular cheilitis, including those who:

  • have an overhang of the upper lip, creating deeper angles at the corners of the lips
  • have regular oral thrush
  • frequently use corticosteroids or antibiotics
  • have sensitive skin
  • have other inflammatory illnesses, such as Crohn’s disease
  • use oral retinoid medication
  • wear braces
  • smoke
  • have anemia, diabetes, or cancer

Because angular cheilitis can be the sign of a fungal or bacterial infection, you should consult your doctor to determine how to treat it. Your primary physician can diagnose angular cheilitis, but dermatologists may be able to provide the best treatment.

Your doctor will examine the skin, and ask about any other skin irritations elsewhere on your body. They’ll likely ask you about your personal and family history of oral thrush and yeast infections. They’ll also ask what other conditions you have, and what medications you’re taking.

Your doctor will likely take culture swabs from the corners of your mouth to send to a lab to test. This will help them definitively diagnose a cause.

While many cases of angular cheilitis are relatively easy to treat, once your doctor identifies an underlying cause, you’ll want to treat it.

If it’s the result of a bacterial or fungal infection — which most are — the infection could spread to adjacent skin. It could also lead to oral thrush.

The underlying cause of angular cheilitis will determine treatment. If your doctor suspects a nutritional deficiency, they’ll likely recommend making dietary or supplement recommendations.

If yeast is present, your doctor will likely prescribe a topical antifungal. Topical antibiotics will be used if a bacterial infection is responsible.

Other treatment options include:

  • topical antiseptics to keep open wounds clean
  • topical steroid ointment
  • filler injections to reduce the creases at the corners of the mouth

You can also use home treatments to treat your angular cheilitis, including:

  • using lip balm regularly to prevent chapped lips
  • applying petroleum jelly or coconut oil to the corners of the mouth, which can form a barrier from saliva

Once your doctor is able to determine the underlying cause of angular cheilitis, it typically responds well to treatment. Many cases won’t even require extra care outside of home treatments on a more regular basis.

If you’ve tried home treatment and your symptoms haven’t resolved after two weeks, make an appointment to see your doctor.