What Are the Causes of Itchy Skin in the Elderly?

Extremely itching skin--also known as pruritus--is a common problem in the elderly and it can also be a maddening one. Anyone who has suffered the temporary itching of an insect bite should sympathize with older people whose skin constantly itches so much they struggle to sleep at night. People with itching skin should not panic--help is available. Of course, identifying the underlying cause of the itch is important, whenever possible, to tailor treatment. In many cases, however, soothing lotions may provide short-term relief.

Atopic Dermatitis

Japanese dermatologist Ryoji Tanei discussed an increasing problem among older people in industrialized societies--senile dermatitis--in his article on atopic dermatitis in the elderly in a 2009 issue of the journal "Inflammation & Allergy-Drug Targets." This is a disorder characterized by itching, dry skin and skin lesions. Tanei says it is more common in older men than women.

Tanei says that one feature that differentiates atopic dermatitis in older people from the disorder in younger adults is that the elderly may have itching in the folds of the knees and elbows, as well as in other parts of the body where younger people experience itching.

In individuals of all ages, atopic dermatitis is caused by an oversensitivity to allergens in the environment that don't bother many people, such as dust mites and pollen. In addition, milk and cheese may also cause atopic dermatitis. Some bacteria have also been implicated as well, particularly Staphylococcus aureus, according to Tanei.

Very Dry Skin

German dermatologist Elke Weisshaar and colleagues, in a 2003 study reported in "Acta Dermato-Venereologica" say that very dry and cracked skin--a condition dermatologists call xerosis--is the most common cause of generalized pruritis. According to the Cleveland Clinic, dry skin in elderly people has many environmental causes that can be corrected, such as excessive use of soaps, too many hot baths, and overheated rooms in the winter and overly air-conditioned rooms in the summer.

When the cause is simple, the solution is relatively simple as well, such as taking fewer and cooler baths and and using milder soaps, as advised by Weisshaar.

Kidney Disease

Kidney disease and kidney failure may cause severe itching, and according to Weisshaar, chronic kidney disease is common among the elderly. Treatment with dialysis--a procedure to move toxins from the body for those with failed kidneys--often leads to itching.

Parasites

Elderly people living in close quarters and unsanitary conditions may develop scabies, which is caused by a tiny parasite. Weisshaar notes that the risk for parasites is increased with institutional care. Lice are another possibility in institutions, especially if the head is extremely itchy.

These parasites can be killed by medications but they recur unless everyone with the problem is treated, including staff and family members who visit.

Imaginary Parasites

When no cause can be found for severe itching, the problem may be in the patient's mind and Weisshaar says that elderly psychotic individuals may develop generalized itching, accompanied by the delusion that parasites are causing this itching.

Australian geriatricians Linda Le and Peter Gonski wrote about this disorder--delusional parisitosis--among elderly patients in the Aug. 18, 2003, issue of the "Medical Journal of Australia." They described an 81-year-old patient convinced she had lice and scabies throughout her body. She had reported her retirement village to the health department as infested with parasites The woman was treated with an antipsychotic medication and her delusions abated.

Le and Gonski note that this disorder is not a phobia and older patients who suffer from it truly believe they are infected with parasites and usually ask dermatologists for help. They also note that a secondary dermatitis can occur with this disorder because patients wash their hands so many times they become raw and irritated--and itchy. Individuals with this problem need psychiatric help.

Shingles

Older individuals who had chicken pox as children are at risk for a re-emergence of the herpes zoster--also known as shingles--and one symptom is extreme itching. According to M. Susan Burke, professor of medicine at Thomas Jefferson University Medical School, up to 50 percent of everyone who survives to age 85 will develop shingles at some point.

An FDA-approved vaccination for those ages 60 and older is available to prevent shingles, but it is unknown how many older people receive this vaccination.

In a study of more than 20,000 military veterans with an average age of 63, Jay R. McDonald of the St. Luis Veterans Affairs Medical Center and colleagues analyzed the risks for developing herpes zoster. They found that key risks were older age and prednisone use.