The difference between fear and fright is that the latter has a sudden and unexpected nature while the former tends to be rather continuous and chronic.
The Kidney opens to the hair. As the hair relies on nourishment from Kidney Essence severe fright might turn the entire hair white in an instant, as the Essence, which nourishes the hair, will be severely depleted by the fright.
As fright disturbs the mind it also affects the Heart - in traditional Chinese medicine the Heart houses the mind. Thus fright consumes the Qi of the Heart, causing severe heart palpitations.
The antidote to fright on a vital and physical levels is to generate strong Heart Qi and sufficient Kidney Essence (to learn more review the materials about the Heart and the Kidney in the Physiology chapter).
Another way to counteract fright is action.