Cracks in the corners of your mouth, sometimes called split lips or cuts at the sides of the mouth, can be painful and slow to heal. This condition is often angular cheilitis. You might find them unsightly, and they may hurt when you talk or eat. It could seem like you just can’t get rid of them.
Norma Cantu, MD, a family medicine practitioner at Banner Health in Torrington, WY, said that these swollen, irritated cracks are often angular cheilitis, also called angular stomatitis. Here’s what to know about this common inflammatory condition.
Angular cheilitis is a common condition that causes inflammation, cracking and sores at the corners of the mouth.
What causes angular cheilitis?
Angular cheilitis is often caused by moisture getting trapped in the corners of the mouth, allowing bacteria or fungi to grow. These cracks develop when saliva collects in the corners of your mouth, and bacteria can start to grow there. They are more common in older people and babies and young children. A lot of factors can lead to saliva buildup in this area:
- Wearing ill-fitting dentures
- Using pacifiers
- Sucking the thumb
- Drooling
- Wearing face masks
- Wearing braces
- Smoking
- Licking the lips
- Having crooked teeth
- Having sagging skin around your mouth from weight loss or aging
There are medical causes for angular cheilitis as well. Causes of angular cheilitis include:
- Anemia
- Diabetes
- Skin allergies
- Down syndrome
- Immune system deficiencies such as HIV (human immunodeficiency virus)
- Vitamin B12,protein or iron deficiency
- Cancers, especially of the kidneys, liver, lungs, pancreas or blood
- Stress
What are the symptoms of angular cheilitis?
In the early stages, you might notice irritation, soreness or red swollen patches at the corner of the mouth or lips. As it worsens, possible angular cheilitis symptoms can include:
- Cracking
- Painful sores
- Dry, cracked or chapped lips
- A burning sensation
- Redness
- Itching
- Scaling
- Swelling
How to heal cracked corners of the mouth fast
To help angular cheilitis heal more quickly:
- Keep the area clean and dry
- Apply petroleum jelly or a protective lip balm
- Avoid licking your lips
- Use antifungal or antibacterial treatments if prescribed
- Stay hydrated
If symptoms don’t improve within a few days, see a health care provider.
How can you prevent it?
To prevent angular cheilitis, you want to eliminate the underlying cause. So, you may want to stop wearing ill-fitting dentures, using pacifiers or thumb sucking if those are causing the condition. Dental care to replace dentures and correct crooked teeth can help. You can also:
- Moisturize your lips instead of licking them
- Quit smoking
- Control diseases such as diabetes or anemia
- Choose a healthy diet to help prevent any vitamin or mineral deficiencies
How is angular cheilitis diagnosed?
Your doctor or dermatologist can diagnose angular cheilitis by examining the area, asking about your symptoms and reviewing your medical history. If they suspect an bacterial infection or a fungal infection, they may swab your mouth and send the sample to a lab for testing. If they think an illness or a nutritional deficiency might be the cause, they may also have your blood tested.
How is angular cheilitis treated?
Treatment depends on the cause, but many cases improve with simple care.
Start with prevention and at-home steps, like keeping the area clean and dry and using lip balm or petroleum jelly to protect the skin.
If symptoms don’t improve, your health care provider may recommend:
- Antifungal or antibacterial medications
- Topical steroid creams to reduce inflammation
- Oral medications in more severe cases
With treatment, most cases clear up within one to two weeks.
“You should seek medical attention if your angular cheilitis is especially painful or starts to spread,” Dr. Cantu said. “Since this problem can resemble other conditions like atopic dermatitis, it should be checked if it is not improving.”
Untreated angular cheilitis can persist and may lead to complications such as skin discoloration or changes in the tissue around the lips.
Frequently asked questions about angular cheilitis
What causes cracks in the corners of your mouth?
Saliva buildup, infections and nutritional deficiencies are common causes.
Is angular cheilitis contagious?
No, but infections that contribute to it can spread.
How long does angular cheilitis last?
With treatment, it often clears within one to two weeks.
Can vitamin deficiency cause cracked lips?
Yes, deficiencies in vitamin B12, iron or protein can contribute.
The bottom line
Cracks in the corners of the mouth, known as angular cheilitis, are common and usually treatable. Addressing the underlying cause and starting treatment early can help symptoms clear quickly and prevent them from coming back.
Need help treating angular cheilitis?
Schedule an appointment with a primary care provider.
Schedule an appointment with a dermatologist.
Other useful articles
- Why You Should Never Ignore That Mouth Sore That Won’t Go Away
- Living With Herpes? What to Know About HSV-1 and HSV-2
- Vitamin B12 Deficiency: Symptoms, Causes and How to Treat It
- Dry Mouth (Xerostomia): Causes, Symptoms and How to Treat It
Content in this article was updatd on May 4, 2026.
