First of all, this is a story I heard from a friend... it's not my own personal experience
OK.. ready? It may sound ordinary, but read it entirely.
I'll sum this one up so it's as sweet and to the point as necessary.
My friend was worried about failing a drug test. He tried the usual crude techniques: drink enough water to dilute, don't take first piss, take mid stream, etc. The one thing 'he' did that most people don't do, or they don't realize is this.... The drug testing company was a very professional, high-tech, and reputable one. So, a day before the test, he called them and actually found out that he could make an appointment and pay for his very own 'personal test' that afternoon. He even inquired as to whether the test would be the same pre-job screening test that is used... and they confirmed it to be IDENTICIAL. Amazingly enough, it was only $40, and the results were emailed rather quickly. AND because it was a 'personal' test, the results were completely confidential and email to him and him only!
Now, not a big deal you say? Think of it like this... Not only do you get the same exact results you will get the following day, but it gives you a 'dry run'. Perhaps there's different techniques you want to try because you might be hot, so you can do that in your own 'personal test'. Because as we all know, these sophisticated test actually test for masking agents too. The point is... spending $40 for a dry run test before the real deal is something you can't go wrong in doing. If you pass, complete and total peace of mind (as long as you follow the same procedure the following day). If you fail... then that's an extra day (or two or three) that gives you time to prepare for a counter-strike.
I'm not implying your test will only be $40, but it shouldn't be much more (or less), and I was surprised by that cheap price too. So, if you're really THAT concerned... take whatever precautions you were planning on taking AND schedule a dry run 1-2 days before the test with a professional & reputable drug testing laboratory... you'll get an idea where you stand.
Haha.... gotta love the system. Yeah, these companies are hired to test for drugs... whether by employers, court orders, or YOURSELF. So, take advantage of your right to test yourself by a professional. Getting an answer and knowing a day or two before the test is definitely worth it!
Hope this helps someone out there!