What are the benefits and side effects of selenium sulfide shampoo?

Generally speaking, selenium sulfide shampoo refers to selenium sulfide lotion. This lotion has functions including antifungal action, dandruff removal, oil control, scalp cleansing, and relief of scalp itching. Its side effects may include dry scalp, dry and fragile hair, contact dermatitis, hair color change, increased hair loss, etc. Detailed analysis is as follows:

I. Therapeutic Effects

1. Antifungal

Excessive proliferation of Malassezia can cause scalp problems. Selenium sulfide lotion has the effect of inhibiting fungal growth. It interferes with the metabolic process of fungal cells and damages their cell membrane structure, thereby inhibiting the proliferation of common scalp fungi such as Malassezia and improving the scalp microenvironment.

2. Dandruff Removal

Under normal conditions, keratinocytes metabolize in an orderly manner. However, in pathological conditions, such as when fungal infection causes inflammation, keratinocyte metabolism becomes disordered, leading to excessive dandruff production. Selenium sulfide lotion exerts a dual antifungal and anti-inflammatory effect, reducing abnormal proliferation and shedding of scalp keratinocytes, thereby achieving dandruff removal.

3. Oil Control

Selenium sulfide lotion can affect the physiological activity of sebaceous gland cells, reducing the activity of enzymes related to lipid synthesis, thus normalizing scalp sebum secretion and improving the oily condition of the hair.

4. Scalp Cleansing

Selenium sulfide lotion has basic cleansing functions. Its components bind to scalp and hair impurities such as dirt, dust, oil, and aged keratin, removing these substances from the scalp and hair during rinsing, thus maintaining scalp cleanliness.

5. Relief of Scalp Itching

Itching is usually caused by irritation from fungi, inflammation, or dirt. Selenium sulfide lotion can reduce factors that stimulate scalp nerve endings from multiple aspects, thereby alleviating scalp itching.

II. Side Effects

1. Dry Scalp

During the cleansing and oil-controlling process, selenium sulfide lotion may excessively remove scalp oils, damaging the natural scalp barrier. When the scalp loses sufficient oil protection, moisture loss accelerates, leading to dryness, tightness, flaking, and even severe cases may cause scalp fissures.

2. Dry and Fragile Hair

Selenium sulfide lotion may also cause moisture and oil loss in hair, making it lose its luster and become dry and fragile. Long-term use can damage the hair cuticle, making hair prone to breakage and split ends, affecting hair appearance and texture.

3. Contact Dermatitis

Some individuals are allergic to selenium sulfide lotion. Upon contact, the immune system may recognize it as a foreign antigen and trigger an immune response. The immune system produces antibodies and releases inflammatory mediators such as histamine, causing symptoms of contact dermatitis on the scalp such as redness, itching, and blisters. In severe cases, symptoms may spread to the face, neck, and other areas.

4. Hair Color Change

For dyed or bleached hair, selenium sulfide lotion may chemically react with certain components in hair dye, causing the dyed color to fade or become uneven, thus affecting the dyeing effect.

5. Increased Hair Loss

Selenium sulfide lotion may affect the normal growth of hair follicles, thereby causing hair growth cycle disorders. Hair follicles cannot provide sufficient nutrition to the hair, making it fragile and prone to shedding, thus increasing the amount of hair loss.

Before using selenium sulfide lotion, carefully read the instructions to understand the correct usage and precautions. If discomfort occurs during use, discontinue use immediately and consult a doctor or professional.