Reactional hair loss is caused by a reaction of an event. It can occur 2 to 4 months after. It can also occur due to processing or a chemical reaction. This increased hair shedding can be caused by high fever, illness, low iron levels, nutrition deficiencies, stress, having a baby, surgery, chemotherapy, a fall or accident to name just some of the causes.
Most of the time, reactional hair loss is usually self-correcting by 8-10 months.