Keep the area clean and dry
Apply petroleum jelly or a thick lip balm frequently
Avoid licking, biting, or picking the corner of the mouth
Use a gentle, fragrance-free moisturizer on the surrounding skin
Avoid spicy, acidic, salty, or very hot foods
Drink plenty of water
Use a soft toothbrush and mild toothpaste
Try an over-the-counter antifungal cream if the area is cracked, red, or persistent
Use a small amount of over-the-counter hydrocortisone only if advised by a pharmacist or doctor
Take a B-vitamin, iron, or zinc supplement only if a deficiency is suspected or confirmed
Replace or clean items that touch the mouth, such as masks, retainers, or mouthguards
See a doctor or dentist if it lasts more than 1 to 2 weeks, keeps coming back, or is very painful
Seek medical care sooner if there is swelling, pus, fever, or spreading redness