What Are the Causes of Itchy Scalp and Hair Loss?

The reasons for itchy scalp and hair loss include excessive dryness of the scalp, inflammation caused by the proliferation of epidermal bacteria, and hair growth through dilated pores. Here are the details:

1. Excessive Dryness of the Scalp Leading to Itching

Many cases of itchy scalp occur during seasonal changes, especially when the environment transitions from humid to dry. The scalp prefers a damp environment and is sensitive to light and wind. Covered by hair and densely populated with sweat glands, the scalp remains warm and moist underneath. Unlike other parts of the skin, the scalp lacks a thick layer of stratum corneum for protection. Therefore, it is prone to excessive dryness and even cracking after exposure to dry air or following shampooing to control oiliness, leading to itching.

2. Inflammation Caused by the Proliferation of Epidermal Bacteria

The scalp is usually warm and damp, well-protected from external contact. However, occasional external contact can lead to scalp injuries, excessive cleaning, unclean contact, pollution, and other factors that disrupt the scalp environment and allow epidermal bacteria to contaminate it. This can easily result in bacterial proliferation. The complex environment of the scalp complicates the process of sterilization and anti-inflammatory treatment, which often causes significant itching, often confined to a specific area, similar to the itching sensation experienced when a wound is healing.

3. Hair Growth Through Dilated Pores

After natural hair loss, the pores on the scalp quickly close due to the pressure from surrounding cells. Therefore, even for those who lose hair, there are usually no obvious holes left on the scalp. However, for those experiencing hair loss, the pores may become blocked, adhered, or closed due to prolonged hairlessness. Removing the blockage at the pore opening or the extrusion of hair growth from below can lead to a noticeable prickling or itching sensation.