The hyponatremia is caused by a relatively smaller loss in total body water. 1  any cause of hypovolemia such as prolonged vomiting, decreased oral intake, severe diarrhea. 2  diuretic use (due to the diuretic causing a volume depleted state and thence ADH release, and not a direct result of diuretic-induced urine sodium loss)
Biotin is safe but is not likely to do much to help your hair grow unless you are deficient in biotin, which is uncommon. A reasonable dose is 5 mg. However, you may get better results by taking a quality multivitamin, eating a healthy diet rich in organic fruits and vegetables, avoid junk food and getting adequate sleep.
The recommended daily intake of biotin for men, women and pregnant females is 30 mcg. If you have difficulty getting enough of this nutrient from consuming biotin-rich foods, such as eggs, nuts, whole grains, beans, fruits and vegetables, talk with your doctor about adding a biotin supplement to your daily regimen.