Dandruff-like «snow on the shoulders» - is an emergence of increased desquamation (a correct removal of the epidermis layer of skin) is manifested as a small white or yellowish color flakes of skin that appear on the surface of scalp and hair. The causes of dandruff are still not completely determined - it may be due to infection, body metabolism violations, digestive disfunctions, stress, nervous tension, poor nutrition, lack of vitamin A and B group in the diet, improper hair care and not suitable cosmetics and many other factors. Some analysts contend that dandruff is caused by the impact of a specific microbe that can cause skin peeling and itching. Although itching scalp may be caused by a skin sebaceous gland excessive sebum on the surface of the skin. As it blocks future sebum access and the  fatty acids, appearing  in the result of the collapse of the secretion of sebum and the process of oxidation, irritate skin nerve endings and result in  itching. The top layer of head skin consists of several dozens of tightly pressed cell layers. Each individual cell passes the path of development - birth, growth and death). When the human body is functioning properly, this process of cell development takes 3-4 weeks, but if something goes wrong the life cycle of cells becomes disrupted - it gets one week shorter. Then those dead cells shed prematurely, thereby creating a «snow on the shoulders».

 

So dandruff is a result of skin cell keratinization violations. Scalp cells update constantly (every 28 days) and we do not even noticed this. These dead skin cells become visible only when a large number of them stick together. One white dandruff flake actually consists of 500 or 1000 dead cells. The cells of the skin stick together because of the sharp increase in the process of of skin cell keratinization, although why this happens has not been clarified yet. It is known that the formation of dandruff is due to increased secretion of the sebaceous glands, so there is an assumption that strong cell keratinization increase is due  to the decay of sebum secretion by the bacterial action. The epidermal outer layer thickens, making it difficult for sebum secretion and the sweat to pass on the surface of the skin, the skin becomes dry and dandruff starts to appear. Currently, a violation of the regular life-cycle of the head skin cells is being associated with increased activity of conditionally patogenous fungus Pityrosporum Ovale or otherwise called Malaseziya Furfur. Under certain conditions, this yeast fungus begins to extend rapidly and promote the premature peeling and shedding of epidermis cells. Although, there is a number of factors in clarifying the conditions triggering the spread of the fungus, such as: vitamin deficiency, immune system weakening, internal organ diseases, body metabolism violations, action of hormones, stress, change of diet, etc. Sometimes dandruff can appear when the head skin is very dry and annoyed by not suitable shampoes or other hair cosmetics, too rapid hair blow drying by hot air or agressive hair chemical treatments, it even may be caused by a stay in a room with very dry air, etc. Such dandruff often disappears by itself as the skin irritation goes away or hair care being changed or modified properly. In such a  case the usage of potentially strong antidandruff treatments can only aggravate the entire situation because there was no problem in a first place.

Quite often in order to determine the cause of dandruff of a specific person, he must undergo a comprehensive medical examination. All the modern means of dandruff (shampoes, lotions, masks, etc.) typically have one or more of the active ingredients to facilitate removal of dandruff. It is wrong to think though, that it is always sufficient to pick one or more means of "medicated chemistry", for example, dandruff shampoo and the problem will disappear. The very specialty of shampoo itself as a product (or any other detergent), which does not remain long on the surface of the head skin and is being washed off with water, can not fully ensure a long-term treatment result on the skin. Depending on the treatment active substances produced action antidandruff "medicated chemistry" can be divided into three groups:

The most common antidandruff active substances used are:

In addition to these components there are popular double-action components, such as Selenium Disulphide has an antifungal and stabilizing action; Coal Tar has keratolytic and stabilizing action. But when it comes to the duration of action of these components, all active substances can be divided into soluble and unsoluble. Soluble components remain active until contact with water (Climbazole, Octopirox, Ketoconozole). Unsoluble components do not dissolve in water and remain valid until the next hair shampoo wash.