Sinus headaches reside in the front of your head, and in your sinus cavities, or behind your eyes. These are caused by a congested toxic liver which creates stress in your bodies ability to handle lymphatic drainage causing allergies, and sinus headaches. These headaches are food allergies such as dairy products, wheat allergies, MSG allergies, and soy allergies all of which create an inflammatory response that increases drainage in the sinus area creating sinus or frontal headaches. Another causes I have found are infections in the teeth that are not found by standard dentist that disrupts the inner ear creating these often frustrating headaches.