Symptoms and signs of dehydration can be minor, such as increased thirst, or severe and life-threatening, depending on the extent of the dehydration. Along with thirst, initial symptoms of dehydration include reduced urine output and darkening of the urine as it becomes more concentrated. If the condition progresses, other symptoms develop, including dry mouth, decreased perspiration, lightheadedness, muscle cramps, weakness, palpitations, and absent tear production by the eyes. The skin may feel cool and clammy. Confusion, organ failure, and coma leading to death eventually occur if dehydration is not corrected.