MY GRANDSON HAS A HUGE BOIL ON HIS BOTTOM. HE

MY GRANDSON HAS A HUGE BOIL ON HIS BOTTOM. HE WAS GIVEN KEFLEX AND CIPRO TO COVER THE BACTERIA. IT HAS STOPPED OOZING. HIS DOCTOR DIDN'T DO A CULTURE. HE SUSPECTS MRSA. HE SAID TO STERILIZE HIS BODY WITH A SOLUTION OF A GALLON OF WATER TO A TBSP OF CLOROX AND LET IT SOAK FOR A FEW MINUTES THEN RINSE HIM OFF. IS THIS A GOOD WAY TO DO THIS? HOW ABOUT AN IODINE SOLUTION? WHAT ELSE WOULD YOU SUGGEST/