I think it takes 2 weeks
Discussion
I just saw a guy on here saying he had them after a few days, two weeks delayed withdrawal symptoms sounds way too delayed when compared to other substances that are much stronger and dangerous.
I have also gone a month or two without and had no withdrawals either.
I guess I was meaning it should be mostly out of your system after two weeks. Withdrawal would likely be before that. Depending on how long you've been doing it and how much, I suppose it could take a month.