Headaches and nausea can be caused by a myriad of conditions, and sometimes they can be difficult to pinpoint. Some of the more common causes, however, include tight muscles in the back and neck, anxiety, alcohol consumption, dehydration, blood pressure problems, and caffeine consumption or the lack thereof. When experiencing these symptoms, it sometimes helps to think about any conditions out of the ordinary that might be causing stress on the head or stomach.
Eye strain is a common cause of headaches and nausea. When staring at a computer screen or printed writing for too long, the eyes can become overstrained, which may lead to headaches. Nausea may accompany the headache if it is severe enough, and lying down in a dark room may remedy the situation. If the eye focuses in one position for too long, the muscles in the eye can tense up, causing the strain that leads to head pain and nausea.
![](http://images.wisegeek.com/slideshow-mobile-small/water-poured-into-short-glass.jpg)
Alcohol is a very common cause of these two symptoms. Consumption of alcohol can cause dehydration, which very often leads to headaches. Further, alcohol in the stomach can affect the stomach lining, which can in turn cause a feeling of nausea. Consuming too much alcohol at one time can also cause nausea, and the stomach may reject the alcohol, leading to vomiting.
![](http://images.wisegeek.com/slideshow-mobile-small/woman-grips-her-stomach.jpg)
The most common cause of headaches and nausea is tension in the neck, shoulders, and back. These tension headaches can occur when sitting in one position for too long, or when straining during exercise or other physical activity. Tension headaches account for the vast majority of all headaches, and can be caused by a number of factors. Stress is one of the most common causes of these headaches, which frequently occur during or after stressful days at work. Caffeine withdrawal and sleep deprivation can also lead to tension headaches; nausea can sometimes accompany tension headaches, causing debilitating discomfort.
![](http://images.wisegeek.com/slideshow-mobile-small/woman-taking-blood-pressure.jpg)
Muscle tension can cause tension headaches as well, and to relieve such pains, stretching is recommended. Moving from a stagnant position can also help, as can drinking water or eating some food. If all else fails, some types of medication may help alleviate the symptoms of headaches and nausea; acetaminophen, ibuprofen, and aspirin are all over-the-counter drugs that may help relieve tension. They should be taken only in recommended doses, however, as these drugs can do harm if taken in too great quantities.