so odor

SO WHEN MY SO GOES TO PEE IT LEAVES BEHIND A STRONG ODOR FOR ALMOST TWO MONTHS NOW THE SMELL IS LIKE THE SMELL OF BOILED EGGS OR SEWAGE, HE DOESNT HAVE ANY PAIN DISCHARGE OR DISCOMFORT JUST THE ODOR.. WHAT COULD IT BE? ALSO HE HAVE BEEN TAKING THE MULTI VITAMINS GERITOL NOT SURE IF THAT COULD BE A FACTOR OR NOT