causes for sudden hair loss in men
1 This type of hair loss usually affects just the scalp, but it sometimes also occurs in beards or eyebrows. In some cases, your skin may become itchy or painful before the hair falls out.  Sudden loosening of hair. A physical or emotional shock can cause hair to loosen.
Hair loss that is genetic is known as androgenetic alopecia and, according to the American Academy of Dermatology, is the most common cause of hair loss. The gene can be inherited from either your mother's or father's side of the family, though you're more likely to have it if both of your parents had hair loss.