Hi i need some advise for my wife. she complains about a constant light headache but no medication takes it a way. what could be the reason ?

Doctor can examine: Most people get a headache at some time, such as from colds, infections, lack of sleep, too much driving, long hours on the computer, stress at work, etc. Over-the-counter drug options include Tylenol (acetaminophen), Motrin, Alleve, Excedrin Migraine, and their generic brands. A severe headache, recurrent headache, persistent headache, or one with other worrisome symptoms should be examined.