While angular cheilitis and cold stores both cause sores on the mouth, they have different causes and treatments. Angular cheilitis is also less common.

If you’ve noticed new red, swollen sores at one or both corners of your mouth, you’re probably wondering whether you have oral herpes.

Oral herpes, a condition caused by the herpes simplex virus, is incredibly common. According to Johns Hopkins Medicine, 50 to 80 percent of U.S. adults carry this virus.

Sores from angular cheilitis are less common than cold sores, but they often look similar. Angular cheilitis causes inflammation, redness, and irritation at the corners of the mouth.

While cold sores are caused by a virus, angular cheilitis can be caused by a number of different things, including fungal infection. Therefore, it requires different treatments.

The first step in eliminating sores at the edges of the mouth is to determine what’s causing them. Read on to learn how to differentiate oral herpes from angular cheilitis and how each is treated.

Both oral herpes and angular cheilitis can cause redness, rawness, and inflammation around the corners of the mouth. However, the sores look slightly different.

Herpes causes fluid-filled blisters that are usually red and bubbly in appearance. They may appear wet or weepy before scabbing and healing. Cold sore blisters tend to clump together in patches on the face, especially in or near the mouth and lips.

Angular cheilitis typically affects the skin at the corners of the mouth, and in some cases it may extend onto the face or lips. However, instead of causing fluid-filled blisters, angular cheilitis usually results in cracked, dry, and irritated skin.

While they may resemble each other, cold sores and angular cheilitis sores have very different causes.

Oral herpes

Cold sores are caused by the herpes simplex virus. Once a person has contracted the virus, they’ll carry it for life. It’s common for those who have the herpes virus to develop cold sores on the face, especially near the mouth.

However, not everyone with the herpes simplex virus develops cold sores. Those who do often experience herpes “outbreaks,” with cold sores forming during times of stress or illness.

Close contact with cold sores — such as through kissing, sharing food, or having oral sex — can pass the herpes virus even before sores become visible.

While herpes can’t be cured, it’s a very common condition, and symptoms can be managed through treatment.

Angular cheilitis

Unlike cold sores, angular cheilitis isn’t caused by a virus, and it isn’t carried for life. It can usually be resolved with treatment.

Angular cheilitis is often caused by a fungal infection from Candida albicans, also called a yeast infection. This fungus may begin growing when excess saliva gathers where the lips meet. This may be the result of poor oral hygiene, improperly fitted dentures, a loss of teeth, or other causes.

Angular cheilitis can also be caused by:

In some instances, a cause can’t be determined. When this is the case, it’s called idiopathic angular cheilitis.

For cold sores, symptoms appear in stages, beginning with redness, inflammation, and discomfort. Angular cheilitis has less defined stages with more overlap of various symptoms.

Angular cheilitis most often occurs in the corners of the mouth, while herpes may affect parts of the face beyond this area, including on the lips, in and around the mouth, and inside the nose.

Cold soresAngular cheilitis
initial redness, swelling, discomfort, itching on skin, on lips, or in the mouth before cold sores emergepainful blisters or cracks in the skin
uncomfortable, fluid-filled blisters (the fluid inside is highly contagious)dryness and crusting of the skin
leaking blisters that turn into wet soresredness
scabbing and healing soresbleeding

It’s not clear why some people with the herpes simplex virus experience more frequent outbreaks than others. However, sometimes treatment can help reduce the frequency and severity of outbreaks, which in turn can reduce the chances of transmitting the virus to someone else.

While angular cheilitis is a temporary problem, it can lead to complications such as impetigo and candidiasis of the skin if left untreated. These complications require further treatment.

Because cold sores are caused by a virus while angular cheilitis is often caused by a fungus, the two conditions require different treatment. Additionally, treating oral herpes is about managing the symptoms, whereas treating angular cheilitis will help the infection go away entirely.

Treating cold sores

While cold sores will heal over time, there are various treatments that can reduce the severity and length of an outbreak. For people with serious outbreaks, prescription antiviral medication, such as ointments and pills, can sometimes help alleviate symptoms.

In some cases, as with the ointment peniciclovir, medications must be used as soon as you notice the first symptoms of a cold sore in order for it to work.

Other treatments for cold sores include:

  • taking over-the-counter pain relievers, such as ibuprofen, to manage discomfort
  • taking over-the-counter anti-inflammatory creams to reduce the swelling and appearance of cold sores
  • wearing sunscreen with an SPF of at least 30 to protect your skin as cold sores are healing
  • regularly cleaning cold sores and keeping the area dry

Treating angular cheilitis

In mild cases, angular cheilitis clears up on its own as long as you keep your mouth clean. But for moderate cases, you can help speed treatment by:

  • applying lip balm or ointment to keep dry, cracked skin moisturized
  • using topical antiseptics to clean the affected area
  • applying topical antifungal cream if you have a yeast infection
  • taking oral antifungal medication if you have a yeast infection
  • applying topical prescription steroid cream to reduce inflammation

If you notice sores on the side of your mouth that worsen or don’t go away over time, it’s probably a good time to schedule an appointment with a medical professional.

They can determine whether you’ll benefit from prescription medications that help heal cold sores and angular cheilitis more quickly.

It’s also possible that you have neither herpes nor angular cheilitis but a completely different condition. A healthcare professional can perform an examination and tests, such as a skin scrape, to help determine what’s causing your symptoms.

Cold sores and angular cheilitis are two different conditions often affecting the corners of the mouth. While they share some symptoms, such as redness, inflammation, and blistering, cold sores are caused by a virus while angular cheilitis is often caused by a fungus.

While each condition tends to resolve on its own, treatment can help speed healing and reduce discomfort. If you have sores on the side of the mouth that don’t go away with time and treatment, schedule an appointment with a medical professional.