I have a random "phantom" itching in the middle of my back in a place I can not reach. I use a comb with a long handle to give him a good scratch. There is no obvious reason – no rash, no irritation or redness, no diagnosed skin disorder. It's annoying, but that does not break my life.
Unfortunately, this is not the case for all who are itching. About 15% of the population suffers from chronic itching, according to Brian Kim, the director of the Center for the Study of Itchiness at the Washington University of Medicine. "This is a very big problem," says Kim. "Studies show that its impact on quality of life is tantamount to chronic pain. Many of my patients, who have both, prefer pruritus pain.
Rockville, Md., Dermatologist Thomas M. Keahey says itching is the major complaint about 20% of his new patients. Also, older patients often raise the issue during their annual skin cancer screening. Most of the time their problems are insignificant, but "sometimes it's a serious request for help," he says.
There are hundreds of reasons why people are itching. They range from dry skin and such skin diseases as psoriasis to contact with dermatitis from rough clothing, pets, soaps, detergents and perfumes, commonly known as eczema, as well as more painful conditions such as bites or poison ivy.
Some people will get into hives after exposure to some external stimulus, such as cold air or sun. "Can you understand that you will explode with itchy hives, walking outside in the cold or sunlight, or after a" healthy "workout?" Keahi says.
There are unexpected reasons, some of them serious. These include diabetes, kidney disease and some cancers. "One thing that can surprise people is that if you have a bad neck or back, it can cause itching due to damage to the nerves that come from your spinal cord," says Kim. "Another thing people may not know is that in rare cases, cancer ̵
Researchers are studying the cycle of itchy scratch, trying to unravel the mysteries of what makes people to itch, then scratch – and keep scratching. Scratching causes damage to the skin that causes inflammation, says Kim. "This increased inflammation, like many rashes, causes more itching in a way that allows for redirection," he says. "So it's a cyclic" scratch-ring "cycle
Kim and others believe the body's immune system is a player." We may think our immune reactions end up in our immune system, "says Kim. "But the itch-scratch cycle involves the immune system with the whole body interacting with behavior and the environment."
Recent studies on mice show that there is a connection between itching and food allergies, which are also an immune response. the skin has led to an increase in the number of activated mast cells – immune cells involved in allergic reactions – in the small intestine, indicating a possible link between food allergies and atopic dermatitis, a type of eczema, according to a study by scientists at Boston Children's Hospital
The brain can also be implicated. another mouse study, researchers from the Chinese Academy of Sciences have shown that tingling with a small part of neurons in a brain region that manipulates sensory information, including pain, can cause or stop scratching in mice, suggesting that these neuros and are associated with itching.
Experts believe that the cycle has evolved over time among animals as a protective behavior.
"Itchy skin plays a key role in detecting harmful substances, especially those that are attached to the skin." researchers Yan-Gang Sun says. "Since itching leads to scratching, it allows the animal to get rid of the harmful substances."
If itching lasts more than a month, it is likely to go to a doctor.
Most people are reluctant to do this for minor itching and resort to medications that are too weak to have any effect, Keahey says. sleeping – or associated with a disfigured rash, people will start entering the dermatologist's office, "he says.
Kim says there are a lot of therapies, but the best ones depend on the nature of the itch: the skin is best helped with moisturizers, whereas if you have eczema, some anti-inflammatory drugs have better anti-itch properties than others .
As for "phantom" itching, who is my dermatologist) and Kim believe that I probably have a rather common disease called nitalia paresthetica, which appears to be itchy but really involves the nerves. the sensitivity of the relay on your back is damaged or not working, causing you, "Kim said. "You are right, this is a little phantom itching because there is no major stimulation in the skin, but the nerve itself is not being prepared, which is why the classic" back "has been invented.