Itching

Definition

Itching is an intense, distracting irritation or tickling sensation that may be felt all over the skin's surface, or confined to just one area. The medical term for itching is "pruritus."

Description

Itching instinctively leads most people to scratch the affected area. Different people can tolerate different amounts of itching, and anyone's threshold of tolerance can be changed due to stress, emotions, and other factors. In general, itching is more severe if the skin is warm, and if there are few distractions. This is why people tend to notice itching more at night.

— Carol A. Turkington

For more information on itching, visit Britannica.com.

Definition

Itching is an intense, distracting irritation or tickling sensation that may be felt all over the skin's surface or confined to just one area. The medical term for itching is pruritus.

Description

Itching leads most people instinctively to scratch the affected area. Different people can tolerate different amounts of itching, and anyone's threshold of tolerance can be changed due to stress, emotions, and other factors. In general, itching is more severe if the skin is warm, and if there are few distractions. This is why people tend to notice itching more at night.

Causes & Symptoms

As of 2002, the recent discovery of itch-specific neurons (nerve cells) has given doctors a better understanding of the causes of the sensation of itching. Another factor that contributes to itching is the release of endogenous opioids in the body. While these chemicals function primarily to relieve pain, they also appear to enhance the sensation of itching. Although itching is the most noticeable symptom of many skin diseases, however, it doesn't necessarily mean that a person who feels itchy has a disease.

Stress and emotional upset can make itching worse, no matter what the underlying cause. If emotional problems are the primary reason for feeling itchy, the condition is known as psychogenic itching. Some people become convinced that their itch is caused by a parasite or some medical disorder. This conviction is often linked to burning sensations in the tongue, and may be caused by a major psychiatric disorder.

Generalized Itching

Itching that occurs all over the body may indicate a medical condition such as diabetes mellitus, liver disease, kidney failure, jaundice, thyroid disorders, and rarely, cancer. Blood disorders such as leukemia, and lymphatic conditions such as Hodgkin's disease may sometimes cause itching as well.

Some people may develop an itch without a rash when they take certain drugs (such as aspirin, codeine, cocaine). Others may develop an itchy, red "drug rash" or hives because of an allergy to a specific drug.

A team of researchers in Texas has discovered that some people infected by Helicobacter pylori, a bacterium that causes gastritis, also develop itching that does not respond to usual treatments. When the bacterium is eradicated from the patient's digestive tract, the itching is relieved.

Itching also may be caused when hookworm larvae penetrate the skin. This type of itching includes swimmer's itch, creeping eruptions caused by cat or dog hookworm, and ground itch caused by the "true" hookworm.

Skin conditions that cause an itchy rash include:

• atopic dermatitis
• chickenpox
• contact dermatitis
• dermatitis herpetiformis (occasionally)
• eczema
• fungal infections (such as athlete's foot)
• hives (urticaria)
• insect bites
• lice
• lichen planus
• neurodermatitis (lichen simplex chronicus)
• psoriasis (occasionally)
• scabies

Itching all over the body can be caused by something as simple as bathing too often, which removes the skin's natural oils and may make the skin too dry and scaly.

Localized Itching

Specific itchy areas may occur if a person comes in contact with soaps, detergents, and wool or other rough-textured, scratchy material. Adults who have hemorrhoids, anal fissures, or persistent diarrhea may notice pruritus ani (itching around the anus). In children, itching in this area is most likely due to worms.

Intense itching called pruritus vulvae (itching of the external genitalia in women) may be due to a yeast infection, hormonal changes, contact dermatitis, or the use of certain spermicides, vaginal suppositories, ointments, or deodorants.

It's also common for older people to suffer from dry, itchy skin (especially on the back) for no obvious reason. Moreover, older people are more likely to develop itching as a side effect of prescription medications. Younger people may notice dry, itchy skin in cold weather. Itching is also a common complaint during pregnancy.

Diagnosis

Itching is a symptom that is quite obvious to its victim. Someone who itches all over should seek medical care. Because itching can be caused by such a wide variety of triggers, a complete physical exam and medical history will help diagnose the underlying problem. A variety of blood and stool tests may help determine the underlying cause.

Treatment

In general, itchy skin should be treated very gently. While scratching may temporarily ease the itch, in the long run scratching just makes it worse. In addition, scratching can lead to an endless cycle of more itching and scratching.

To control the urge to scratch, a person can apply a cooling or soothing lotion or cold compress to the area. Itching may be relieved by applying a warm compress of diluted vinegar, preferably such herbal vinegars as plantain, violet, lavender, or rose.

The itching associated with mosquito bites can be reduced by applying meat tenderizer paste, table salt (to wet skin), or toothpaste. Any alkaline preparation (like a paste of baking soda and water) will help ease the itch.

Probably the most common cause of itching is dry skin. Flaxseed oil and vitamin E taken orally can help to rehydrate dry skin and can reduce itching. There are a number of simple things a person can do to relieve itching.

• Don't wear tight clothes.
• Avoid synthetic fabrics.
• Don't take long baths.
• Wash the area in lukewarm water with a little baking soda.
• Take a lukewarm shower for generalized itching.
• Try a lukewarm oatmeal (or Aveeno) bath for generalized itching.
• Apply bath oil or lotion (without added colors or scents) right after bathing.

Practitioners of Chinese medicine utilize a wide variety of herbs as well as acupuncture and ear acupuncture to treat itching based upon the cause. The medicine Xiao Feng Zhi Yang Chong Ji (Eliminate Wind and Relieve Itching Infusion) can be taken three times daily to relieve itching. For external treatment of itching, the patient may bathe in Zhi Yang Xi Ji (Relieve Itching Washing Preparation) and apply She Chuang Zi Ding (Cnidium Tincture) and Zhi Yang Po Fen (Relieve Itching Powder).

Emotional stress can trigger many different dermatoses, including certain itching rashes. Hypnosis has been helpful in treating atopic dermatitis, itching, psoriasis, hives, and other dermatoses.

In several small studies, transcutaneous electrical nerve stimulation (TENS) has been effective in temporarily relieving chronic itch associated with varying dermatoses. TENS is a treatment in which mild electrical current is passed through electrodes on the skin to stimulate nerves and block pain signals. Portable TENS units are available for home use.

Cutaneous field stimulation (CFS) was found to safely relieve experimentally induced itching for a longer time period than TENS. CFS electrically stimulates nerves in the skin to harmlessly mimic scratching and inhibit the itch sensation.

Herbal Itch Remedies

The following herbal remedies for itching are used externally:

• aloe vera
• bracken juice
• bird-of-paradise (Strelitzia reginae) flowers
• cabbage leaf poultice
• cattail (Typha latifolia) juice
• chickweed (Stellaria media) salve
• comfrey (Symphytum officinale) juice
• evening primrose (Oenothera biennis) oil
• heal-all (Prunella vulgaris) juice
• honeysuckle vine flowers and leaves
• marigold (Calendula officinalis)
• marsh mallow (Althaea officinalis) leaf poultice
• myrrh (Commiphora species) oil
• oats (Avena sativa) bath or poultice
• onion juice
• papaya fruit
• plantain (Plantago major) juice or poultice
• red pepper juice
• Sage (Salvia officinalis) leaves
• St. John's wort (Hypericum perforatum)
• tea tree (Melaleuca alternifolia) oil
• yellow dock (Rumex crispus) tea bath

Allopathic Treatment

Specific treatment of itching depends on the underlying cause. Such antihistamines as diphenhydramine (Benadryl) can help relieve itching caused by hives but won't affect itching from other causes. Most antihistamines also make people sleepy, which can help patients sleep who would otherwise be awake from the itch. Newer antihistamines that do not make people drowsy as a side effect are also available to treat itching.

Creams or ointments containing cortisone may help control itching from insect bites, contact dermatitis, or eczema. Cortisone cream should not be applied to the face unless a doctor prescribes it, and should not be used over the body for prolonged periods without a doctor's approval.

A newer medication that relieves the itching associated with burns as well as speeding the healing process is called dexpanthenol. Dexpanthenol helps to relieve the itching by preventing the affected skin from drying out.

Expected Results

Most cases of itching go away when the underlying cause is treated successfully.

Prevention

Soaps are often irritating and drying to the skin and can make an itch worse. They should be avoided or used only when necessary. People who tend to have itchy skin should:

• Avoid bathing daily.
• Use lukewarm water when bathing.
• Use mild soap.
• Pat (not rub) the skin dry after bathing, leaving some water on the skin.
• Apply a moisturizer immediately after the bath but avoid lanolin products.
• Use a humidifier, particularly during heating season in colder climates.

Eating garlic and onion and taking vitamin B supplements may help to repel mosquitoes. Application of cedar, sage, pennyroyal, rosemary, artemisia, or marigold to the skin may also repel mosquitoes

Resources

Books

Turkington, Carol A., and Jeffrey S. Dover. Skin Deep: An A to Z of Skin Disorders, Treatments and Health. New York: Facts on File, 1998.

Ying, Zhou Zhong, and Jin Hui De. "Cutaneous Pruritus." Clinical Manual of Chinese Herbal Medicine and Acupuncture. New York: Churchill Livingston, 1997.

Periodicals

Black, A. K., and M. W. Greaves. "Antihistamines in Urticaria and Angioedema." Clinical Allergy and Immunology 17 (2002): 249-286.

Ebner, F., A. Heller, F. Rippke, and I. Tausch. "Topical Use of Dexpanthenol in Skin Disorders." American Journal of Clinical Dermatology 3 (2002): 427-433.

Kandyil, R., N. S. Satya, and R. A. Swerlick. "Chronic pruritus associated with Helicobacter pylori." Journal of Cutaneous Medicine and Surgery 6 (March-April 2002): 103-108.

Nilsson, Hans-Jörgen, Anders Levinsson, and Jens Schouenborg. "Cutaneous Field Stimulation (CFS): A New Powerful Method to Combat Itch." Pain 71 (1997): 49-55.

Schmelz, M. "Itch—Mediators and Mechanisms." Journal of Dermatologic Science 28 (February 2002): 91-96.

Shenefelt, Philip D. "Hypnosis in Dermatology." Archives of Dermatology 136 (March 2000): 393-399.

Stander, S., and M. Steinhoff. "Pathophysiology of Pruritus in Atopic Dermatitis: An Overview." Experimental Dermatology 11 (February 2002): 12-24.

Tang, William Yuk Ming, Loi Yuen Chan, Kuen Kong Lo, and Tze Wai Wong. "Evaluation of the Antipruritic Role of Transcutaneous Electrical Nerve Stimulation in the Treatment of Pruritic Dermatoses." Dermatology 199 (1999): 237-241.

Yoon, S., J. Lee, and S. Lee. "The Therapeutic Effect of Evening Primrose Oil in Atopic Dermatitis Patients with Dry Scaly Skin Lesions Is Associated with the Normalization of Serum Gamma-Interferon Levels." Skin Pharmacology and Applied Skin Physiology 15 (January-February 2002): 20-25.

Organizations

American Academy of Dermatology. 930 N. Meacham Rd., PO Box 4014, Schaumburg, IL 60168. (708) 330-0230.

[Article by: Belinda Rowland; Rebecca J. Frey, PhD]

Definition

Itching is an intense, distracting irritation or tickling sensation that may be felt all over the skin's surface or confined to just one area. The medical term for itching is pruritus.

Description

Itching instinctively leads most people to scratch the affected area. Different people can tolerate different amounts of itching, and the threshold of tolerance can change due to stress, emotions, and other factors. In general, itching is more severe if the skin is warm and if there are few distractions. This is why people tend to notice itching more at night.

Demographics

It is common for children to be itchy occasionally. Prolonged itching in a specific location and generalized itching in many different areas of the body are less common.

Causes and Symptoms

The reason for the sensation of itching is not well understood. While itching is the most noticeable symptom in many skin diseases, it does not necessarily mean that a person who feels itchy has a disease.

Stress and emotional upset can make itching worse, no matter what the underlying cause. Itching is often worse at night or at times when there are no distractions. If emotional problems are the primary reason for the itch, the condition is known as psychogenic itching. Some people become convinced that their itch is caused by a parasite; this conviction is often linked to burning sensations in the tongue and may be caused by a major psychiatric disorder.

Generalized Itching

Itching that occurs all over the body may indicate a medical condition such as diabetes mellitus, liver disease, kidney failure, jaundice, thyroid disorders, or rarely, cancer. Blood disorders such as leukemia and lymphatic conditions such as Hodgkin's disease may sometimes cause itching as well.

Some children may develop an itch without a rash when they take certain drugs such as aspirin or codeine. Others may develop an itchy red drug rash or hives because of an allergy to a specific drug such as penicillin.

Itching also may be caused when any of the family of hookworm larvae penetrate the skin. This includes swimmer's itch and creeping eruption caused by cat or dog hookworm and ground itch caused by the true hookworm.

Many skin conditions cause an itchy rash. These include:

• atopic dermatitis
• contact dermatitis
• dermatitis herpetiformis (occasionally)
• eczema
• fungus infections (such as athlete's foot)
• hives (urticaria)
• insect bites
• lice
• lichen planus
• neurodermatitis (lichen simplex chronicus)
• psoriasis (occasionally)
• scabies

Itching all over the body can be caused by something as simple as bathing too often, which removes the skin's natural oils and may make the skin too dry.

Localized Itching

Specific itchy areas may occur if a person comes in contact with soap, detergents, or wool or other rough-textured, scratchy material. Adults who have hemorrhoids, anal fissure, or persistent diarrhea may notice itching around the anus (called pruritus ani). When children itch in this area, the cause is most likely pinworms.

Intense itching in the external genitalia in women (pruritus vulvae) may be due to candidiasis (yeast), hormonal changes, or the use of certain spermicides or vaginal suppositories, ointments, or deodorants.

When to Call the Doctor

If the child is itchy all over or has a localized itch in combination with a rash, fever, infection, or is acting sick, the doctor should be contacted.

Diagnosis

Itching is a symptom that is obvious to its victim. Because itching can be caused by such a wide variety of triggers, a complete physical examination and medical history will help diagnose the underlying problem. A variety of blood and stool tests may be needed to help the doctor to determine the cause of the itch.

Treatment

Antihistamines such as diphenhydramine (Benadryl) can help relieve itching caused by hives but will not relieve itching from other causes. Most antihistamines also make people sleepy, which can help children sleep who would otherwise be awakened by the itch.

Specific treatment of itching depends on the underlying condition that causes it. In general, itchy skin should be treated very gently. While scratching may temporarily ease the itch, in the long run scratching makes the itch worse and can lead to an endless cycle in which scratching an itch makes it more itchy.

To avoid the urge to scratch, a cooling or soothing lotion or cold compress can be applied when the urge to scratch occurs. Soaps are often irritating to the skin and can make an itch worse; they should be avoided or used only when necessary.

Creams or ointments containing cortisone may help control the itch from insect bites, contact dermatitis, or eczema. Cortisone cream should not be applied to the face unless prescribed by a doctor.

Probably the most common cause of itching is dry skin. There are a number of simple things that can be done to ease the annoying itch:

• Do not wear tight clothes.
• Avoid synthetic fabrics.
• Take shorter baths.
• Wash the area in lukewarm water with a little baking soda.
• For generalized itching, take a lukewarm shower or oatmeal (or Aveeno) bath.
• Apply bath oil or lotion (without added colors or scents) right after bathing.

Children who itch as a result of mental problems or stress may benefit from seeing a mental health expert.

Prognosis

Most cases of itching resolve successfully when the underlying cause is treated.

Prevention

There are certain things people can do to avoid itchy skin. Children who tend toward itchy skin should take the following steps:

• Avoid a daily bath.
• Use only lukewarm water when bathing.
• Use only gentle soap.
• Pat dry, not rub dry, after bathing, leaving a bit of water on the skin.
• Apply a moisture-holding ointment or cream after the bath.
• Use a humidifier in the home.

Children who are allergic to certain substances, medications, or foods can avoid the resulting itch if they avoid contact with the allergen. Avoiding insect bites, bee stings, poison ivy, and similar plants can prevent the resulting itch. Treating sensitive skin carefully, avoiding overdrying of the skin, and protecting against diseases that cause itchy rashes are all good ways to avoid itching.

Parental Concerns

Children who are itchy should have their finger nails cut short to help ensure that they do not scratch the itchy area enough to create breaks in the skin. Scratching until the skin is broken can lead to infection. Itching can be very frustrating, and, if it is severe, it can interfere with normal activities such as studying or sleeping. Itching is a symptom of many common childhood ailments such as chickenpox and contact with poison ivy, as well as of some more serious conditions.

Resources

Books

Fleischer, Alan B., Jr. The Clinical Management of Itching. New York: Parthenon Publishing Group, 2000.

Yosipovitch, et al., eds. Itch: Basic Mechanisms and Therapy. New York: Marcel Dekker, 2004.

Periodicals

Moses, Scott. "Pruritus." American Family Physician 68 (September 15, 2003): 1135.

Yosipovitch, Gil, and Jennifer L. Hundley. "Practical Guidelines for Relief of Itch." Dermatology Nursing 16 (August 2004): 325–30.

[Article by: Tish Davidson, A.M. Carol A. Turkington]

Pruritus; an unpleasant cutaneous sensation, provoking the desire to scratch or rub the skin.