Xerosis (Dry Skin)

What happens in xerosis

The outermost skin layer, the stratum corneum, acts as a barrier. Its cells are held together by a mix of lipids (ceramides, cholesterol and fatty acids), and it contains natural moisturizing factors that hold water. In xerosis:

• lipids are reduced or stripped away
• natural moisturizing factors decrease
• water evaporates faster (increased transepidermal water loss)
• dead skin cells stick together and shed in visible flakes

When the barrier cracks, irritants enter and nerves are exposed, causing itching and inflammation. Scratching then damages the barrier further.

Asteatotic eczema

When xerosis becomes inflamed, it is called asteatotic eczema or eczema craquelé. The skin, often on the shins, develops a pattern of fine red cracks resembling crazy paving or a dry riverbed, and is itchy and sore. It is common in older adults in winter.

Causes and risk factors

Environmental

• low humidity, cold weather and indoor heating
• hot showers and long baths
• harsh soaps, detergents and alcohol-based sanitizers
• swimming in chlorinated water
• sun exposure and wind

Age

Over age 60, the skin makes less oil, fewer lipids and less natural moisturizing factor. Most older adults have some degree of xerosis, and it is a leading cause of itching in this age group.

Skin conditions

• eczema (atopic dermatitis)
• ichthyosis, an inherited tendency to very dry, scaly skin
• psoriasis
• contact dermatitis

Medical conditions

• hypothyroidism
• diabetes
• chronic kidney disease, especially on dialysis
• liver disease
• HIV and some cancers, such as lymphoma
• malnutrition and deficiencies of zinc, essential fatty acids or vitamin A

Medicines

• diuretics
• statins
• retinoids such as isotretinoin and acne creams
• certain cancer treatments, especially EGFR inhibitors
• topical steroids used long-term (thin skin)

Symptoms

• rough, dull or ashy-looking skin
• fine flaking or larger scales
• tightness, especially after bathing
• itching, often worse at night and in winter
• fine lines, cracks and fissures, which may bleed, especially on hands and heels
• redness and soreness when inflamed

For a broader look at what dry, peeling, scaly or rough skin can mean, see skin dryness, peeling, scaliness or roughness.

Diagnosis

Xerosis is diagnosed by examining the skin. A doctor will ask about bathing habits, products, climate, medicines and other symptoms. If dryness is widespread, severe or unexplained, blood tests may check thyroid function, blood sugar, kidney and liver function, and nutrition. A skin scraping or biopsy can rule out fungal infection or other conditions.

Treatment

Moisturize effectively

• Apply within 3 minutes of bathing, while the skin is still slightly damp, to trap water.
• Choose thicker products: ointments (petroleum jelly) and creams in tubs work better than thin lotions.
• Look for helpful ingredients: - humectants draw in water: glycerin, urea, lactic acid, hyaluronic acid - emollients smooth the skin: ceramides, fatty acids, shea butter - occlusives seal moisture in: petroleum jelly, dimethicone, lanolin (some people are allergic)
• Urea 10 to 20% or lactic acid 12% creams soften thick scaling on legs, heels and elbows. They can sting on cracked skin.
• Moisturize at least twice daily, and more often for hands.

Bathing habits

• limit showers to 5 to 10 minutes in lukewarm water
• use a gentle, fragrance-free, soap-free cleanser, only where needed
• pat skin dry instead of rubbing
• avoid bubble baths and scented products

Environment

• run a humidifier in winter
• wear gloves outdoors in cold weather and for washing dishes
• choose soft, breathable fabrics like cotton, and avoid wool directly on the skin

For inflamed or very itchy skin

• a short course of medium-strength steroid ointment for asteatotic eczema, as prescribed
• treat any infection
• antihistamines that cause drowsiness may help sleep but do not treat the itch itself, and should be used cautiously in older adults

Treat underlying causes

Controlling thyroid disease, diabetes or kidney disease, adjusting medicines and correcting nutritional deficiencies all help.

Complications

• itch-scratch cycle and lichenified (thickened) skin
• cracks that let bacteria in, leading to infection such as cellulitis
• asteatotic eczema
• poor sleep from itching

Frequently asked questions

What is xerosis?

Xerosis is the medical term for abnormally dry skin. It occurs when the outer skin layer loses water and protective fats, causing roughness, flaking, tightness and itching. It is very common in older adults and in winter.

What causes xerosis cutis?

Common causes include cold, dry air, hot showers, harsh soaps, aging and frequent handwashing. It can also be linked to eczema, ichthyosis, hypothyroidism, diabetes, kidney disease, malnutrition and medicines such as diuretics, statins and retinoids.

What is the best treatment for xerosis?

Apply a thick, fragrance-free moisturizer containing ceramides, glycerin, urea or lactic acid right after bathing and at least twice a day. Take short, lukewarm showers with a gentle cleanser, and use a humidifier in winter.

Why does dry skin get worse in winter?

Cold outdoor air holds little moisture, and indoor heating lowers humidity further. Hot showers, which are more tempting in winter, strip skin oils. Together these increase water loss from the skin, making dryness and itching worse.

When should I see a doctor for dry skin?

See a doctor if dry skin does not improve after 2 weeks of moisturizing, itching disturbs your sleep, you develop red cracked patches or signs of infection, or you have other symptoms such as tiredness, weight changes or excessive thirst.