Itching is a common and often irritating sensation that can be caused by a variety of factors. Dr. Arndt from Harvard Health explains that aging can trigger itching as the skin barrier becomes less effective, leading to increased absorption of irritants. The immune response of the skin also changes, with reductions in fat and blood flow altering its reaction to external factors.
In recent studies, several immune system cells, including mast cells, basophils, and helper T cells, have been identified as key players in creating the itch sensation. These cells are involved in inflammation, which is the redness and swelling that occurs in the body in response to various triggers.
A study by the Center for the Study of Itch at Washington University School of Medicine in St. Louis discovered that individuals experiencing unexplained itching may have previously unrecognized defects in their immune system. This research suggests that irregularities in the immune system could be the reason behind the urge to scratch.
Hormonal changes during menopause and pregnancy can also lead to skin dryness and itching, often feeling more intense at night. Medications such as antibiotics, blood pressure pills, opioids, and diuretics, along with skin care products like soaps, deodorants, or bug repellents, are other potential culprits. In rare cases, nighttime itching could indicate more serious health issues.
Eczema, or atopic dermatitis (AD), is often described as “the itch that rashes.” It usually starts with itching, followed by a rash, and the discomfort can persist. In the U.S., around 9.6 million children and 16.5 million adults suffer from AD, significantly impacting their quality of life.
A mosquito bite, for instance, causes the body to release histamine in the affected area, leading to redness and itchiness. Antihistamines can alleviate this itch by preventing histamine from binding to receptors in the skin. However, widespread itching is often a sign of internal organ diseases.
For more detailed information on the causes and solutions for persistent itching, visit the following sources:
Harvard Health
Harvard Science in the News
Washington University in St. Louis
