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).
Bumps on the scalp can be brought about by a skin condition known as seborrheic dermatitis. According to the doctors, the illness happens due to the yeast malassezia and an excess production of oil on the skin. Triggers can include stress, infrequent bathing, alcohol that has lotions and obesity.