Why do I get constant headaches?

Chronic daily HA. Chronic daily headache is the official name for this and the previous poster summed up many of the causes. Another significant cause is NSAID use (ibuprofen, aspirin, aleve). Using these medications more than a cpl times a week can result in daily withdrawal headaches. The solution: stop taking them! it hurts for a cpl days but then gets better. Be sure to have your vitamin levels checked too.
Neurology Exam. Constant headaches are relatively rare. The causes are multiple including: trigeminal neuralgia, migraines, tumor/space occupying lesion in the brain, medications, sleep deprivation, metabolic imbalance, occupational or home exposure to toxin, neck problems, cluster headaches, rebound from one of the medications currently utilized, meningitis/encephalitis, etc. A neurologist should sort this out.
Get checked out. A good start at finding potential headache triggers would be to maintain a diary. Every time you have a headache write down what you were doing, the foods you ate that day, alcohol, smoking, caffeine, stress, how much sleep you had the night before, eye strain, etc. Try to find patterns in your headache so that you can learn what things to avoid. Get checked by your doctor.

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Why do I get constant headaches? I thought it was my sight so I got my eyes checked and got glasses. Headaches stopped for awhile. Now they're back.

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Why do I keep getting constant headaches on the side of my head? Job or close work?

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