Headaches are one of the most common symptoms with which patients present to doctors. The multi million dollars over the counter headache remedies is proof of that. Headaches may be the forerunners for a variety of ailments, and hence anyone suffering from a constant headache should consult an eye specialist. Most people believe that eyestrain and the need for glasses are very common causes of headache. However, this is not true: need for glasses is not the commonest cause for headache.