if you have receding hairline then its 99% male pattern baldness, get propecia, if no receding hairlane check hormones(cortisol,thyroid), deficiency in minerals,vitamins, fungi infections of scalp.
get shampoo with zinc pyrithione and it should go in a week. i had the same thing for more than 2 years, lost like 50% of hair all over scalp, sheeding decrased from 100,200 hair a day to 10-20, still no new regrowth.