THE human skin, just like any other organ, experiences a number of physical changes with age. Common changes related to ageing are the appearance of wrinkles, pigmentation and sagging. These do not cause much problems but may be aesthetically displeasing.
Xerosis, also known as dry skin, is a common problem which often presents with itchiness. The genetic variant of xerosis is usually associated with eczema and is experienced from childhood.
The adult onset of dry skin usually occurs due to age-related changes in the skin. However, those with extensive dryness or those who fail to respond to conventional therapy may require a physical examination and investigation to rule out any possible underlying causes such as thyroid disease or malignancies.
Why does xerosis occur?
As age progresses, hormonal influence on the sebaceous or oil glands in the skin results in decreased production of sebum, which acts as a natural moisturiser. This causes the skin to appear dry and lustreless in contrast to the young, who tend to have oily skin.
This condition is experienced both by men and women as they reach 50 to 60 years of age.
In women, these changes often occur after menopause. As age progresses, these changes result in patches of fine white scales which make the skin appear powdery. This is commonly seen on the legs especially over the shin, back of trunk and lateral aspects of the thighs and arms, causing itchiness in these areas.
In some cases, dryness and itchiness is more generalised and experienced throughout the entire body.
At times, the skin may appear to have superficial cracks (eczema craquele), which, if untreated, may progress to produce fissures. These fissures and the process of scratching causes breaches in the skin, resulting in redness (inflammation) and secondary bacterial infection.
Those with a genetic predisposition to dry skin, that is endogenous eczema, may experience an outcome that is worse.
Frequent washing, bathing, hot water baths and using perfumed or medicated soaps may aggravate the dryness and worsen itchiness. These strong soaps often lather excessively and remove natural oils along with the dirt on the skin, leaving it squeaky clean and dry (skin feels tight).
Mild soaps designed for sensitive skin or baby soaps can be used instead. The excessive use of air-conditioners without humidifiers accompanied with the use of cholesterol lowering agents may contribute to the dryness of skin.
Dryness becomes worse when the climate is arid or when travelling to countries during the winter, where the environmental humidity is low.
How to treat xerosis?
The primary step in the management of this condition is to avoid dryness by regularly applying moisturiser to the skin. Emollients or moisturisers are best applied immediately (within three to five minutes) after a bath to retain the moisture on the skin.
Both water and oil-based moisturisers can be used, depending on individual preferences. Most products are available over the counter without a prescription.
Some of the common emollients include aqueous creams, urea creams, soft paraffin and petroleum jelly. Natural oils, such as olive oil and coconut oil, may also be used.
Oil may be applied during or after a bath. Lotions are commercially available in bottles with dispensers while creams and ointments are distributed in jars or tubes.
Creams are emulsions generated from mixing oil and water. Lotions contain more hydrating components compared to creams or ointments but its hydrating effect does not last very long (about five to six hours) hence it requires frequent reapplication. It is best applied two to three times a day or as required.
Increasing the proportion of oil in the emulsion enables the moisturising effect to last longer, hence it may be used once or twice a day (lasts about six to 12 hours).
Too much moisturiser applied in a thick layer may cause discomfort especially in warm temperatures or when the individual sweats. Some individuals may develop skin irritation to cream-based moisturisers as they may be allergic to the preservatives in these preparations.
In this case, an oil-based emollient or ointment may be used instead, as it has lower preservative content.
Deciding on which type of product to use generally depends on the skin type and individual preference. Combining different products, such as cream for day use and ointment for night use may be beneficial. However, the best product is one that the individual prefers and is willing to use regularly.
Intense itchiness and scratching causes redness of the skin (inflammation) and may require a short term application of a mild to moderate topical corticosteroid on the affected area.
An oral antihistamine may also be taken to provide symptomatic relieve.
Once the inflammation reduces, the steroid can be discontinued and the skin moisture can be maintained with a topical moisturiser according to the individual’s preference.
Dietary intake on its own has minimal influence on improving the dryness of the skin. It is a common misperception that increasing oral fluids or eating certain foods alone may help prevent dry skin. The body absorbs the required amount of water and nutrients from the dietary intake and the excess is excreted.
However, it is important to have a healthy balanced diet which contains fresh fruits, vegetables and adequate amounts of water for a healthy life and properly functioning body.
Understanding the reasons for dry skin and how to care for the skin will help improve this condition.
One of the main barriers to management is a poor understanding of the skin, leading to poor compliance to topical treatment. Some even consider the application of moisturiser as time-consuming and unpleasant as it may be messy.
Here are some skin care suggestions to prevent dryness:
- Avoid frequent washing or baths.
- Avoid very hot baths as hot water tends to remove natural oils from the skin surface. Lukewarm water may be used instead.
- Avoid strong soaps. Use a mild soap or cleanser preparation used for infants or special formulations with moisturising properties commonly used for eczema. Cleansers should be used sparingly, concentrating mainly on areas with a lot of sweat, such as the armpit, neck and genitals. If the routine is bathing twice a day, then a cleanser may be used once in the evening while plain water is used in the morning.
- Regular (two to three times a day) application of moisturisers is encouraged depending on the level of skin dryness.
- Moisturisers are best kept in the washroom and applied immediately after bath for best results.
Associate Prof Dr Leelavathi Muthupalaiappen is a lecturer and consultant family medicine specialist at Universiti Kebangsaan Malaysia. Her areas of interest include family medicine and dermatology.