Dan­druff causes fre­quent irri­ta­tion, inflam­ma­tion and itch­ing in the scalp. Indi­vid­u­als that that expe­ri­ence this type of irri­ta­tion and itch­ing in the scalp, often tend to scratch the area to relieve itch­ing. Scratch­ing the scalp fre­quently weak­ens the roots of the hair. This even­tu­ally leads the hair to fall out. A per­son can develop dan­druff due to sev­eral rea­sons such as, over intake of sugar and fats, exces­sive expo­sure to sun­light, per­spi­ra­tion, and in some case it may be due to genetic prob­lems. If the pres­ence of dan­druff is not due to genetic rea­sons, it can be treated effec­tively. The most effec­tive over– the– counter treat­ments avail­able are the anti-dandruff sham­poos and con­di­tion­ers which con­tain chem­i­cals such as zinc pyrithione and sele­nium sul­fide. After wash­ing hair with these par­tic­u­lar prod­ucts, the chem­i­cal is left on the scalp. These chem­i­cals pre­vent the regrowth of the fun­gus caus­ing the dan­druff on the scalp, and hence the hair is pro­tected from hair loss asso­ci­ated with the dandruff.