Many headaches are due to trigger points in the mid-upper back, which are knotted up tissue that restricts blood-flow and gives you a headache. This is especially true if you seem to get a headache worse on one side of your head. If this sounds like you I recommend searching for trigger points, and possibly investing in a Thera-cane to help you reach places like your back that you can't get to yourself. Trigger points are so tricky and deceptive because the pain they cause is nearly always in a different location than the trigger point itself. I also recommend looking into an acupressure mat for your back to lay on daily for $30 or less. Headaches and many other symptoms are caused from something as simple as trigger points and not many people know this. Just thought I'd spread the word out there and let curezone know what worked for me and hopefully it can help others too.