Cracked Mouth Corners vs Allergic Contact on Lips

Angular cheilitis causes inflamed fissures at one or both mouth corners. Allergic contact cheilitis is lip eczema caused by a delayed reaction to a contact allergen.

Research updated 2026-10-23

dry, scaly inflamed lips and lip margins, in a lower-face view turned to the person’s right on light skin.

Key differences What is it?What it looks like Diagrams When it starts Triggers Daily Care Treatment Outlook Complications When to get help Questions

Key differences

The same eight facts on every condition comparison.

Usual age

Any age

Where

Corners of the mouth

Lips and nearby skin

Main sign

Red, cracked mouth corners

Dry, scaly, itchy lips

Itch or pain

Sore

Itchy or burning

Contagious

Long term

Clears with treatment; can recur

Clears when the trigger is avoided

Scars

Who gets it

Dentures, lip licking, deep folds

Anyone sensitized to a lip product

What is it?

Cracked Mouth Corners

Allergic Contact on Lips

What is it?

What it is
Angular cheilitis causes inflamed fissures at one or both mouth corners.

What it is
Allergic contact cheilitis is lip eczema caused by a delayed reaction to a contact allergen.

What it looks like

Cracked Mouth Corners

One corner of a mouth with a red crack and rough surrounding skin.

Cracked Mouth Corners A small fissure interrupts the skin where the lips meet.

Allergic Contact on Lips

Dry, reddened lips with a pink irritated border around the mouth.

Allergic Contact on Lips Redness and flaking extend from the lips onto the nearby skin.

Skin tones

dry, scaly inflamed lips and lip margins, in a lower-face view turned to the person’s right on medium skin.

dry, scaly inflamed lips and lip margins, in a lower-face view turned to the person’s right on brown skin.

dry, scaly inflamed lips and lip margins, in a lower-face view turned to the person’s right on deep skin.

In the skin

Saliva and repeated wetting weaken the barrier at the mouth corners. Candida or bacteria can contribute to inflammation in the damaged skin.

After sensitization, the immune system reacts to a substance contacting the lips. Ingredients in lip products, toothpaste or other exposures can trigger the resulting inflammation.

When it usually starts

010203040506070+

Cracked Mouth Corners. Can develop at any age.

Allergic Contact on Lips. Can start at any age after relevant exposures or barrier damage.

Causes and triggers

Causes

Saliva exposure damages the barrier; Candida or bacteria may contribute.

Sensitisation to ingredients in lip products, toothpaste or other contacts produces inflammation.

Risk factors

Saliva pooling, Dentures, Nutritional deficiency in some cases

Flavourings, Fragrances, Lip cosmetics, Dental products

Trigger

● Cracked Mouth Corners

● Allergic Contact on Lips

Lip licking

Can contribute

Not listed

Persistent moisture

Can contribute

Not listed

Contact with a relevant allergen

Not listed

Can contribute

Daily Care

Cracked Mouth Corners

Allergic Contact on Lips

Daily care

Habits that help

Apply a plain protective ointment to the sore corners
Reapply after eating or washing to reduce saliva contact.
Reduce lip licking and gently pat away pooled saliva
Repeated wetting keeps the corners irritated.
Keep teeth and dentures clean
Ask a dentist to check dentures that fit poorly or allow saliva to collect.
Rinse the mouth after an inhaled steroid if instructed
Keep using the inhaler as prescribed; ask about technique if problems recur.
Seek review if cracks persist or recur
Yeast, bacteria, dental fit or a nutritional problem may need specific treatment.

Avoid

Avoid: Picking crusts or stretching the cracks open
This delays healing and can introduce infection.

Habits that help

Apply plain petrolatum or a bland fragrance-free lip balm
Reapply when dry and before bed; stop any balm that burns or makes the rash worse.
Keep saliva off the lips and surrounding skin
Try a gentle reminder or replacement habit instead of repeatedly licking sore lips.
Simplify lip products while the skin heals
Avoid flavored, fragranced or irritating products and introduce replacements one at a time.
Protect lips from wind and sun
A tolerated SPF lip balm and physical protection help outdoors.
Check labels against confirmed patch-test allergens
Toothpaste, cosmetics and dental products can contain triggers; keep the clinician’s safe-product list.
Follow the allergic contact on lips care plan
Use plain petrolatum and avoid suspect lip products. Patch testing can guide avoidance.
Discuss allergen or irritant review
Persistent lip eczema may need examination and patch testing rather than repeated product changes.

Avoid

Avoid: Biting, peeling or scrubbing loose skin
This reopens cracks and delays healing.
Avoid: Repeatedly trying medicated balms without a diagnosis
Persistent cracking or rash may need assessment for allergy, infection or another cause.

Treatment differences

Evidence labels come from each condition’s own treatment list.

Treatment

● Cracked Mouth Corners

● Allergic Contact on Lips

Over-the-counter

Plain petrolatum barrier

Listed

Protects against saliva and repeated wetting.

Plain petrolatum

Listed

Protects the lip barrier; choose an unflavoured, fragrance-free product.

Prescription topicals

Cause-specific topical treatment

Listed

A clinician may select an antifungal, antibacterial or anti-inflammatory if examination supports it.

None listed

Outlook

Long term

The corners often improve when moisture, irritation and any infection are addressed. Recurrence is possible if the underlying contributor remains; persistent cracking needs reassessment.

Lip eczema can improve once the relevant allergen is identified and avoided. The allergy tendency remains, so renewed exposure can bring the rash back.