That just goes to show whats been said all along here: niacin is a myth. It does nothing to help pass a U/A. People that claim that niacin helped them pass were also drinking copius amounts of fluids, which is known as dilution. These people have passed by merely diluting the THCA concentration to where the urine sample registered a negative. These people wouldve passed anyway, just on the dilution factor alone and without the niacin to go with it.

Besides, taking more niacin than the 15 mg RDA can have some serious health consequences.
Overdoing Niacin Can't Thwart Drug Abuse Tests and Is Risky

Misusing Vitamin To Foil Drug Test May Be Toxic; Plus, It Doesn't Work

It must be understood that dilution techniques (regardless of configuration) are far from being 100% fail-safe. They can backfire if the THCA concentration in the bladder is too high. For most heavy smokers, it would be virtually impossible to dilute that concentration enough without sending the S/G and creatinine levels into a downward spiral and sending up the red flags at the lab.


For your next test, you should just cut to the chase and quit taking chances with your own urine - substitute, with either a clean persons sample or synthetic. This is the way to go, since youve stressed that you cannot fail another test. Employment-related U/As are unobserved unless you had been suspected of tampering.