Dehydration Sudden weight loss, dark urine (decreased, not increased urination) Decreased 24-hour urine; in mild and moderate dehydration: normal blood sodium; in severe dehydration: increased blood sodium | Dehydration Sudden weight loss, dark urine (decreased, not increased urination) Decreased 24-hour urine; in mild and moderate dehydration: normal blood sodium; in severe dehydration: increased blood sodium |