It is possible to cause sore eyes when dehydration happen, but not often. Dehydration is easy to cause dry eye. The eye depends on the flow of tears to provide constant moisture and lubrication to maintain vision and comfort. If eyes cannot produce adequate and quality tears, then you may suffer pain, redness, burning, a gritty sensation and a feeling of a foreign body or sand in the eye. All these symptoms are similar with sore eyes in that dry eyes along with sore eyes. When you dehydration, drink a lot of water may do little help with recovery. The best thing to do is to see a doctor and take infusion in time. By the way, if you suffer sore eyes, you can seek medical attention. Contact your health care provider or an eye doctor for an exam of your eyes immediately. No matter what kind of eye problems you got, you must take good care of them and consider healing them as soon as possible.