Angular cheilitis is a skin condition that causes pain and inflammation on one or both corners of the mouth. There are several ways to treat angular cheilitis and its accompanying symptoms.

The technical term for the affected areas is the labial or oral commissures. The commissures refer to the corners of the mouth, where the upper and lower lips connect.

Angular cheilitis (AC) is inflammation — including redness, swelling, fissures, cracks, crust-like film — and pain at one or both of the commissures.

The inflammation associated with AC may slightly extend onto the lips or skin but primarily affects the corners of the mouth.

This article examines the treatments, causes, risk factors, and complications of angular cheilitis.

Fast facts on angular cheilitis:

  • Angular cheilitis is not a disease but a symptom of something else.
  • Excess moisture on the lips or mouth can lead to the condition.
  • Anyone of any age can develop angular cheilitis.
  • Treatment involves addressing the underlying cause quickly.

AC is sometimes called angular stomatitis, cheilosis, or perleche and causes pain in the corners of the mouth.

AC itself does not spread beyond the corners of a person’s mouth. But if it is infected and not treated, the infection can spread elsewhere on a person’s body. However, this condition is not contagious and will not spread to other people.

Due to the risk of infection, a doctor should determine the cause of the inflammation to treat it correctly.

Symptoms of AC occur at or around the corners of a person’s lips and mouth. These include:

  • painful cracks or fissures
  • swelling
  • pain and burning sensation
  • redness
  • blisters
  • bleeding
  • crusting
  • erosions

In some cases, there is no clear cause of AC. However, it often begins when the corners of someone’s mouth stay moist for too long. People may then lick their lips, which dries the corners of the mouth and leads to AC. Rubbing or licking the infected area can worsen the issue, intensifying the pain.

The irritated areas may crack open or peel and can sometimes bleed. In some cases, the dry, cracked skin can become infected.

Candida, or yeast, is a common cause of infection that can make the area itch or burn.

Common bacterial infections — including staph and strep — can also occur. There may even be multiple infections. For instance, a person can have both a yeast and a bacterial infection known as polymicrobial infection.

Other causes of AC may include:

  • collection of saliva causing irritant dermatitis
  • an overhang of the upper lip, resulting in deep furrows at the corners of the mouth
  • dry, chapped lips
  • proliferation of bacteria, yeast, or a virus

Depending on the cause and providing it is not infected, AC is highly treatable. A person’s symptoms usually improve within 1–2 weeks of treatment.

There are several ways to treat AC and its symptoms:

Dietary and lifestyle changes

AC is an oral manifestation of iron, vitamin B12, and folate deficiency.

A 2021 research study showed that 25% of people with AC were low in vitamin B and iron. A person with a vitamin and possible mineral deficiency can benefit from these supplements.

Doctors recommend people take vitamin supplements and replacements and follow a balanced diet if AC develops due to poor nutrition. Deficiencies in a person’s diet and the absorption of essential vitamins and nutrients, such as zinc, can also lead to AC.

Doctors also recommend people avoid tobacco smoking, which can contribute to AC.

Antibiotics and antifungal

With an infected area, the underlying infection requires topical or oral treatment.

It is important for a doctor to diagnose the cause of the infection since yeast infections, for example, will not respond to antibiotics. In most cases, a doctor can determine whether the infection is bacterial or due to yeast by looking at the area. However, doctors may also take a sample from the corner of the mouth and examine it under a microscope to establish fungal, bacterial, or viral growth.

Depending on the results, doctors will either prescribe:

  • a topical antibiotic for 1–2 weeks
  • antifungal medications applied to the corners of the mouth 3 times daily for 2 weeks
  • oral antiviral medication

In combination with the antimicrobial treatment, a doctor might also prescribe a low-dose topical steroid to help reduce inflammation. A person can apply this to the skin to aid healing.

Long-term emollient therapy, oral antibiotics, or oral antifungals may be necessary in severe or recurrent cases.

Hygiene

The main treatment for all cases of AC is for people to keep the area clean and dry. A person should avoid licking the area and not allow saliva to sit in the corners of the mouth. A lip balm, petroleum jelly, emollients, or protectant can treat AC when doctors have not identified the cause or to prevent AC from occurring from the outset.

Fillers and injections

Ill-fitting dentures or poor bite may be causes of recurrent AC. If these occur despite dental realignment, a person may need to consult a dentist to re-fit dentures.

Doctors may also recommend injectable fillers such as collagen, which can help with droopy lips that cause AC and help turn the corners of the mouth upwards. This makes saliva less likely to accumulate.

Some people may mistake AC for a cold sore. However, AC usually only affects the corners of the mouth. Cold sores occur anywhere along the lip or lip line — not usually in both corners of a person’s mouth.

Cold sores usually begin as an itchy or painful area leading into a group of small, painful blisters. AC starts as a patch of dry or irritated skin at the corners of the mouth. Untreated, it can progress into swollen and painful patches that may bleed.

Unlike angular cheilitis, cold sores are contagious and can pass on to someone else through close contact.

The herpes simplex virus causes cold sores, which antiviral drugs can treat, while AC has various causes and treatments.

Most people with AC have at least one risk factor.

Diabetes can weaken the immune system, making it more vulnerable to the yeast infections associated with AC. Many people with diabetes develop skin problems, including infections. Diabetes can also damage a person’s gums and teeth, leading to tooth loss and dentures and further increasing the risk of AC.

Other risk factors include:

  • Sensitivity and allergies: People who have allergic dermatitis or a history of atopic dermatitis tend to be more sensitive to:
    • dental care products, such as toothpaste and mouthwash
    • nickel in orthodontic braces
    • certain ingredients in lip cosmetics
    • certain ingredients in acne products
    • specific foods, due to flavorings and preservatives
  • A weak immune system: For example, HIV and AIDS and chemotherapy treatment can affect a person’s immune system.
  • Genetics: Having a genetic condition, such as Down syndrome.
  • Nutritional issues: These include anemia or a poor diet, both of which can make the body more vulnerable to certain infections.
  • Thrush: A yeast infection of the mouth.
  • Tooth and gum issues: Wearing dentures, particularly if they are badly fitting or having a poor bite.
  • A virus or infection in or near the mouth: For example, a cold sore.
  • Very dry and chapped lips: If the lips are so dry they crack open, it is easier for viruses, bacteria, and yeast to invade.
  • Vitamin and mineral deficiencies: These include people with vitamin B, zinc, and iron deficiencies, which can affect older people and those who have had bariatric surgery. It can also affect individuals who have the following conditions:

Untreated, AC can lead to yeast or other infections. If the cause of AC has not been diagnosed or a person continually develops angular cheilitis alongside other symptoms, they should seek medical evaluation.

If home remedies such as petroleum jelly do not help AC or symptoms worsen, a person should consult a doctor.

Some people may develop recurring AC, and further infections are likely when AC risk factors remain. This means that people with diabetes, unusual lip anatomy, or other risk factors should take action to prevent future infection. Some strategies people can follow to prevent AC include:

  • keeping the lips dry
  • avoiding licking lips
  • treating an underlying condition
  • using lip balm
  • practicing good oral hygiene

AC refers to inflammation — including redness, swelling, fissures, cracks, crust-like film — and pain at one or both corners of the mouth. The condition is sometimes preventable.

People who experience frequent AC should consult their doctor about potential causes. A person can also explore the possibility of dietary or lifestyle changes, such as using lip balm during winter, which may avoid an occurrence.