Recently, a young woman complained of sore lips and a rash on her chin. Her doctors treated her with antibiotics and creams for five years without improvement. Upon examination, I saw redness on the sides of her chin and her lips were dry and cracked. Upon further questioning, she revealed that she chose products with cinnamon in her toothpaste, chewing gum, candies and pastries.
Based on her history and clinical findings, my impression was contact dermatitis to cinnamic aldehyde. Cinnamon, as well other flavors and fragrances, contain the compound. Decades ago, the widespread use of cinnamon toothpicks lead to the recognition of contact dermatitis. I recommended the use of fragrant free baking soda toothpaste, and the avoidance of any compounds with flavors and fragrances, as mouthwash, candies, chocolates, and ice cream.
Chapness occur more frequently than contact dermatitis of the lips . People experience chapped lips, either from lip licking or mouth breathing. Allergic individuals, who have atopic eczema, upper respiratory asthma or sinus problems, frequently mouth breathe and lick their lips. Lip balm, lip conditioner, or Acquaphor is helpful to control the sore lips.
Additionally, cracking in the corners of the mouth, called angular cheilits or perleche, causes lip irritation. The derivation of perleche comes from french, meaning “to lick”. Gravity lowers the corners of the mouth and thus facilitates a moist environment, whereby yeast infections develop. Licking the corners of the mouth, poorly fitting dentures, and vitamin deficiencies, including niacin, vitamin B12, folate, and zinc, can cause cracks in the corners of the mouth.
Also, ultraviolet light damages lips and causes soreness with precancerous changes or actinic chelitis. Smoking frequency causes leukoplakia or precancerous changes as well. The lips appear white, mottled, crusted, or with cracks. These pre-cancerous conditions require SPF30 lip balm protection and prescribed therapy to reverse the changes. Therapies recommended include creams, photodynamic therapy, and laser.
When left untreated, squamous cell skin cancer of the lip may develop and has the potential to metastasize and even lead to death.
Furthermore, cold sores or herpes simplex infections, lichen planus, and autoimmune conditions cause sore lips.
Multiple conditions contribute to lip soreness. If Aquaphor, lip balm, or lip conditioner does not improve the condition, a visit to your doctor is worthwhile.