Dehydration
Dehydration is when the body does not have enough water or fluids to perform optimally. This condition is common [1] among people suffering from nausea, vomiting, diarrhea, or excessive exercise. These conditions and activities tend to divert blood away from the organs to the muscles, causing the volume to decrease, which may cause hypotension. Vomiting and diarrhea are the leading causes of dehydration and may be dangerous if the patient does not recoup all the lost fluids.
Other less serious causes of dehydration include exercise, sweating, fever, and heat exhaustion or heat stroke. The early stage of dehydration may cause thirst and dry mouth, and it may progress to more serious symptoms, including lightheadedness, dizziness, or fainting. These severe symptoms are a sign of low blood pressure and if prolonged, may lead to life-threatening conditions, including stroke, kidney failure, confusion, acidosis, coma, and death.