- Health A to Z
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.
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 doesn't necessary 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 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 (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.
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
- chickenpox
- 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
On the other hand, 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.
 |
Author Info: Carol A. Turkington, The Gale Group Inc., Gale, Detroit, Gale Encyclopedia of Medicine, 2002 |
Related Learning Centers |
 |
Advertise | Terms of Use | Privacy Policy