This has come up a thousand times on this site.
I have it on good authority - Dr. Drew Pinsky, host of Loveline - that the only thing that really works is time, and unfortunately THC takes more time to get out of your system than anything else.
If using the niacin makes you feel better ... well, it's your money. The only sure way is to not use in the first place. And that isn't a judgement, simply a fact.
I do wish you Luck. Back in my day, no one really worried about marijuana. Now places go ballistic over it.
Well it worked fine for me, on my last test, but im no nutritionalist, and niether is Dr Drew.will slo niacin work to clean thc in a week