Itching is an intense, distracting irritation or tickling sensation that maybe felt all over the skin's surface, or confined to just one area. The medical term for itching is "pruritus."
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.
The reason for the sensation of itching is not well understood. While itchingis the most noticeable symptom in many skin diseases, it doesn't necessarilymean 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 is a condition that occurs all over the body that may indicate a medical condition such as diabetes mellitus, liver disease, kidneyfailure, jaundice, thyroid disorders (and rarely, cancer). Blooddisorders such as leukemia, and lymphatic conditions such as Hodgkin'sdisease 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 cator 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)
- Fungus infections (such as athlete's foot)
- Hives (urticaria)
- Insect bites
- Lichen planus
- Neurodermatitis (lichen simplex chronicus)
- Psoriasis (occasionally)
On the other hand, itching all over the body can be caused by something as simple as bathing too often, which removes the skins natural oils and may makethe skin too dry and scaly.
Localized itching refers to specific itchy areas that may occur if a person comes in contact with soap, detergents, and 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"). In children,itching in this area is most likely due to worms.
Intense itching in the external genitalia in women ("pruritus vulvae") may bedue to candidiasis, hormonal changes, or the use of certain spermicides or vaginal suppositories, ointments, or deodorants.
It's also common for older people to suffer from dry, itchy skin (especiallyon the back) for no obvious reason. Younger people also may notice dry, itchyskin in cold weather. Itching is also a common complaint during pregnancy.
Itching is a symptom that is quite obvious to its victim. Someone who itchesall 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 testsmay help determine the underlying cause.
Antihistamines such 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 otherwisebe awake from the itch.
Specific treatment of itching depends on the underlying condition that causesit. 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 itch--scratch--moreitching.
To avoid the urge to scratch, a person can apply a cooling or soothing lotionor cold compress when the urge to scratch occurs. Soaps are often irritatingto 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 appliedto the face unless a doctor prescribes it.
Probably the most common cause of itching is dry skin. There are a number ofsimple things a person can do to ease the annoying itch:
- Don't wear tight clothes
- Avoid synthetic fabrics
- Don't take long baths
- Wash the area in lukewarm water with a little baking soda
- For generalized itching, take a lukewarm shower
- Try a lukewarm oatmeal(or Aveeno) bath for generalized itching
- Apply bath oil or lotion (without added colors or scents) right after bathing.
While most cases of itching go away when the underlying cause is treated successfully, people who itch as a result of mental problems or stress should seek help from a mental health expert.
There are certain things people can do to avoid itchy skin. Patients who tendtoward itchy skin should:
- Avoid a daily bath
- Use only lukewarm water when bathing
- Use only gentle soap
- Pat dry, not rubdry, 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.
Patients who are allergic to certain substances, medications, and so on can avoid the resulting itch if they avoid contact with the allergen. Avoiding insect bites, bee stings, poison ivy and so on 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.