Headaches, a common complaint among travelers can have many different causes. Most headaches can be easily treated by a mild pain relief medication but sometimes finding the source of the headache can help prevent a repeat. Some common causes of travelers headaches include dehydration, lack of sleep, sleeping in uncomfortable positions (especially sitting up in a seat on a plane or bus), heat and sun exposure, and excess alcohol consumption. Some causes are easier to prevent than others but always having some water available and drinking frequently may help with many causes. Also consider bringing travel pillow to make that uncomfortable place a little more tolerable.