My dad has a renal problem and has been undergoing dialysis for more than 2 years now. Last June he was confined for a month in the hospital due to tuberculosis of the spine. The doctor gave him ethambutol without giving us prior advice that it may lead to a problem in his vision. I would like to know if there is the best, safest and fastest way to cure this. I really want to help him because he is now suffering depression because of the said illness. Thank you.