One of the main causes of sinus drainage is simply being alive. Every day the human body produces several liters of sinus fluid and mucus, and all of that natural liquid must go somewhere.
It is a area of tenderness of the scalp in which people also sometimes feel stabbing headaches. Others just feel very sore and tender to the touch. It is felt to be caused by irritation of the connective tissue which attaches the muscles of the scalp to the skull (cranium).
When you can feel with your fingertips an area on your scalp with thick and stubborn skin peels or when you have yellow dandruffs that sticks on your scalp for long time and sometimes you feel stimulation on the scalp area.