AC is the acronym for actinic cheilitis and is a condition where the lower lip becomes dry, rough, and thick with scales. It is mainly caused by the excessive exposing of the lips to the sun, and for this reason actinis cheilitis is also known as solar cheilitis.

It mostly affects men above 20 years of age, the elderly (as they work outdoors mostly), and people who mostly reside in hot tropical regions and dry places like deserts, compared to women and children. The people who are at risk include those with low immunity, of fair complexion, and those who have undergone transplant of an organ.

Once diagnosed, it is important to go for treatment for this disease as early as possible. Initially, treatment may cause some pain, swelling, and other effects, but these are cured after completion of the therapies. There are many methods for treatment of AC, including carbon dioxide laser vaporization, electrosurgery and cryosurgery.

Closeup view of cheilitis founded in an Asian male child. Image Credit: Karan Bunjean / Shutterstock

Symptoms of Actinic Cheilitis

In the initial stages, the symptoms may not be noticeable, but slowly after a month or a year they appear. One may experience many problems on the lower lips. Some of the common of symptoms of AC are:

• Dry lips: the lips become dry in the first stage. Dryness of lip means lack of moisture.
• Color of lips: lips are usually red in color, but for those who have AC the lips appear abnormally red or the color of the lip may not be uniform. Some parts of the lip turn white and pale.
• Soreness: in the beginning the lips pain and have unexplained lesions.
• Swelling: an abnormal enlargement of lips may happen due to accumulation of fluids.
• Thickening of lips: owing to swelling, the lips appear thick, especially in the lower part.
• Loss of demarcation: the sharp line or border in the lips disappears.
• Cracked lip: as it becomes dry, people face problems of frequent cracking and bleeding on their lower lip.
• They face difficulties like bleeding especially during applying lip products.
• There is a possibility of extension of the disease to other part of the body like on the face or around the lips.
• When the condition becomes worse, the patient experiences an itching and burning sensation.
• The person may face difficulties in eating, chewing, and swallowing.    

Major Causes of Actinic Cheilitis

Exposure to sun

Ultra violet (UV) rays from the sun are harmful radiation, and the major cause of AC. There are three types of ultraviolet rays; UV-A, UV-B, and UV-C. The layers of the atmosphere prevent or filter these harmful rays. UV-C which lies in the range of 100–290 nm are almost completely prevented by the atmospheric layers and UV-A and UV-B which lies in the range of 320–400 nm and 290–320 nm, respectively, penetrate the atmosphere and contribute to the causes of AC. Among the two UV radiations (UVA and UVB), UVB plays a major role in inducing AC.

Excessive exposure to UV radiation leads to an altered epidermis layer of cells and subsequently results in damage to DNA in the epithelial cells of the lips. When commutative ultraviolet radiation is exposed to the skin, it leads to the suppression of the activities of antigen present in the cell and weakens the immune system. This in turn leads to the detection of cellular damage and DNA mutation.

People who have low melanin are very prone to get affected by AC. Such people have lighter skin, which may be very sensitive to sun exposure. This may cause sunburns which are then associated with may related factors that support AC.

Other Minor Causes of Actinic Cheilitis

Some of the minor causes of AC are:

• Tobacco: Tobacco, as well as smoking, is a contributor to the minor causes of AC. Tobacco and cigarettes contain toxic substances, which lead to the condition of AC and other related diseases like mouth ulcers and further to mouth cancers. people with frequent or long use are at high risk of AC compared to lesser users.
• Poor oral hygiene: Keeping the mouth clean and free from any kind of mouth disease is the best practice of oral hygiene. One should follow regular brushing and cleaning of teeth.
• Allergen substance: There are many varieties of cosmetic products used on the lips like lip balm and lipstick; such products contain chemical substances. These strong chemical substances may produce allergic reactions and irritation on the lip and cause AC or worsen it.
• Ill-fitting dentures: Ill-fitting dentures do not actually have an effect on AC; however, the prolonged use of poorly fitting dentures can cause intense irritation, infection, and inflammation, all of which may lead to AC.