Medicated Hair shampoos are used to correct any disorder of secretion in the scalp. If you have dry hair, choose a shampoo based on cod oil, tar or lecithin. If you have oily hair, a shampoo containing sulphur or essence of cedar is best. Thereare dry and colouring shampoos widely used in western countries. Dry shampoos come in an extremely fine powder form which is sprinkled over the hair and then removed by very thorough brushing. Their main advantage is that no wetting of the hair is required. They consist of a mixture of synthetic detergent in powder form and mineral salts. Mostly sodium salts are used which absorb fatty matter. Thus the hair can be cleaned without too frequent washing, and because of this they are particularly recommended for oily hair.

Colouring shampoos have become very popular in recent years for brightening the colour of the hair. They are in fact good shampoos with a detergent base to which has been added either a bleach or a dye which is much less harmful than the real dyes because it does not penetrate the: hair but only covers it with a thin colouring film.

Colouring shampoos are generally harmless, but they can affect those who are susceptible to allergies, by causing an eczema on the face and swelling or irritation on the scalp. To avoid these severe allergies, do not use colouring shampoos during periods, pregnancy, menopause, ovarian upsets, and skin troubles.