The itchiness in your scalp and the white flakes on your clothes can only mean one thing: dandruff. This skin condition can be caused by any number of things like stress, a dry scalp, or it may be eczema, or it might be caused by an overgrowth of a fungus called malassezia. To get rid of dandruff, you may want to try a new shampoo with a milder formula. You may even turn to a special dandruff shampoo that has ketoconazole, selenium sulfide, or Zinc pyrithione. If the condition persists, you can ask your doctor for special dandruff