Sore Throat

From an e-mail correspondence:

My son sings and one day he had a concert and he had a horse throat and it was sore also and his teacher told him to drink a small amount of his urine before the concert and he thought his teacher was crazy but he did it because he couldn’t talk the morning of the concert and to my disbelief, it worked. We were told that a lot of singers do this when their throats act up before a concert. Just a thought on urine.