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How to treat headaches at the base of the skull (cervicogenic headaches )
Maintain good posture.
While sitting and standing, it's incredibly important to maintain proper posture to avoid pressure on the spine. Less pressure on your spine will help your cervicogenic headaches improve, as this is where the stress originates.
Though it will take conscious effort initially, over time, good posture will just become habit. While sitting, consider supporting your back with a pillow or a rolled towel.