Without going into full detail, I recently agreed to take random drug screenings. I have to call in every day and randomly I am selected to come in and pee in a cup. I quit medicating on 02-25-13 and failed my first screening on 02-26-13 to nobody's surprise. On 03-06-13 I took a 12 hour masking cleanse and started a regiment of 2oz. of cider vinegar a day. I shoot a 1oz. shot of vinegar chased with coffee in the morning and when I get home I shoot another 1oz. shot with a beer back. On 03-07-13 I passed my first test. Again on 03-13-13 I passed. So then I decided to roll the dice and see how far I could take this. On 03-15-13 I medicated with 2 glass pipes full, on 03-16-13 4 glass pipes and on 03-17-13 2 more glass pipes. Still continuing my vinegar shots daily. Yesterday on 03-19-13 I was called in for a screening. Less than 48hrs. after medicating last!!! So far still good!!!!
Passing a drug test is easy.
Your first and best option is to buy synthetic urine. That is how I passed. Very rarely do places test for that because it's too expensive.
If you don't want to use store bought synthetic urine for whatever reason I am going to tell you something very important for you to know; there is no way to do a quick detox and get the marijuana out of your system faster. It's there for as long as it's going to be there and there is nothing you can do to significantly speed it up. Not vinegar, not juice, not niacin, not anything. Your best bet is to dilute your urine. There are threads on the internet on how to properly do it.
Your goal should not be to get all the marijuana out of your system, rather it should be to not have the batch of pee that comes out test positive. Without doing additional research these are the steps I remember researching about:
1) If you know you will be tested stop smoking is possible. Short of having the marijuana completely out of your system there is no guarantee you will pass. Not smoking will increase your chances of passing the test, although if you get regular random test you may find yourself not smoking quite a bit.
2) Aside from not smoking, there isn't much you can do to get the marijuana out of your system. Drinking fluids before the day of the test does NOTHING. The marijuana is stored in your fat cells and they escape and get into your urine. Drinking liquid will make it so a high level of THC does not appear in the batch of pee, but it's still in your body. This is why fat people need longer to get the THC out of their system. That being said, being active and burning fat BEFORE the day of the test can help, however, the day of the test you should not be too active because you want the THC to stay in your fat rather than being in your pee
3) Starting four hours before the test drink a big glass of water. Then wait 2 hours and start drinking water every 15 minutes until 45 minutes before your test (I don't remember if this is the exact formula. I'm sure you can google it, but the point is to get your water clear). When your pee is clear you would automatically pass. The problem is they know this trick and if your pee is yellow you automatically fail. That's where step 4 comes in
4) Take a vitamin B supplement (Might be vitamin b12 specifically not sure. I think you should take it about an hour and a half before, but I don't remember the exact timing). The vitamin B turns your urine bright yellow so they never suspect a thing
5) Try to squeeze in 1-2 pees with the yellow urine from the vitamin supplement. One is enough, try not to go more than twice.
6) When you pee into the cup only use the middle of the stream. Pee a little into the toilet first, then catch some in the cup, then pee the remainder in the toilet. That way a the smallest amount of THC will come out.
If you do that you have pretty good chances of beating this. I know someone who takes test regularly and has always passed with this method (Or a very similar version since I don't recall some details), but this is still not a 100% guarantee. Should be over 90% if you do it right from what I have seen though. Good luck!