How do I pass a drug test?
I'm glad you asked. Here's the thing; I'm a guy who smokes pot and passes drug tests. What separates me from the heard is that I not only pass drug tests but I understand how drug tests work.
There's a lot of B.S. info on the nets these days (and from your worthless hippie friends) on how to pass a drug test. Luckily for y'all I know all about such things. Completely unrelated to my new job I've recently put in a lot of time studying how to pass urine based drugs tests. This information is only for people who have been legally prescribed marijuana by the state but still have to pass a urinalysis, for non-court related reasons. I'm assuming you're having some kind of "drug-free pee" contest with your friends.

First off, most things you've probably heard about passing drug tests are false. Sure, your friend may have taken niacin for 2 weeks and passed his/her drug test but the niacin had nothing to do with it. You could skip counter clockwise everyday for a month and pass a drug test, that doesn't mean skipping actually aided you in passing.

Here are things that don't work:
Niacin
Golden Seal
Cranberry Juice
"flushing" your system in any way
anything that "detoxes" your system

Basically anything you take to flush pot out of your system is a scam. THC is fat soluble. You can not flush it out. You can not detox it out. You can however get less fat. Exercise does indeed help, as does not being a fat ass.

There are no hard and fast rules for lessening the concentration of THC in your system. It varies greatly depending on how fat you are, how much exercise you get and how fast your metabolism is. The half life of THC, in your system, can be anywhere from 1 day to 2 weeks. Conceivably a heavy smoker could have a concentration of 1000 ng/ml and get down to the needed 50 ng/ml in under 5 days while another heavy smoker could take months. The best thing to do is to stop smoking marijuana. Yes, it's a bummer but such is life.

What if you did stop? What if you stopped two weeks before your first interview but the interviewer took one look at your awesome hair and hired you on the spot? What if you then had to take a pre-employment drug test within 24 hours? err... I mean "drug-free pee" contest. Well, then you've come to the right place.

There are three main methods to beating a urine based drug test; don't do drugs, use someone else's urine or dilute your own urine. Method A doesn't really need any explanation. Method B works, but I consider it cheating. As always, I like to pick C, good ol dilution.

You know those drinks you can buy for $50? You know, those drinks that promise results or your money back? Well, that's the dilution method. The only thing is, you don't need the drink and you don't need to spend $50 bucks. Just follow the steps below.

As Soon As You Know You Will Have A Drug Test

Stop doing drugs. If the drug test is more than 3 days away then start exercising. Cardio is a good idea. Drinking water won't help, taking anything at all won't help. If there are more than 3 days until your drug test the only thing that will help is exercise.

3 Days Until Your Drug Test

Take a home drug test. They cost 10-15 bucks at your local Walgreens. Test yourself using your first pee of the day. If it says you're good then you probably don't have to do anything further. If not...

Load up on creatine. Your body takes at least 36 hours to turn creatine into creatinine. May as well start loading up now. You can purchase creatine at a fitness store or you can just start eating more red meat. Either way.

Stop exercising. At this point we no longer want to be encouraging the THC out of your system. The more you're burning out of your fat the more that will be in your urine.

Day Of Test

Have a big breakfast, lots of fat, protein and fiber. Your first pee of the day is the most cannabinoid concentrated so try to schedule your test for the afternoon.

4 Hours To Go

Drink a pint of water then a half pint ever half hour for the next 2 hours.

2 Hours To Go

Drink a quarter to half pint of Gatorade ever time you pee. If your worried about your pee not being yellow then take a dose of B complex with each Gatorade dose. It doesn't really matter but if yellow pee makes you feel better then go for it.

At The Drug Test

Don't pee right into the cup. Pee a bit into the toilet then into the cup. We're looking to give the middle pee here.

After The Drug Test

Don't smoke pot. Your results could come back diluted and you could be screwing yourself by not waiting a few days. You should hear back within a week.

Why this works:
Exercise: Burns fat which helps the THC metabolites out of your system.
Creatine: Turns into Creatinine which is checked to determine the validity of your sample.
Gatorade: Adds salt to increase the specific gravity, which is checked to determine the validity of your sample.
Water: There are cannabinoid metabolites in your system, you can't change that. What you can do is add water to your system so the amount of thc metabolites per ml of urine is lessened. Your basically turning malt liquor into Pabst.

Info:
If you received almost no notice and just want to buy some time you can drink the hell out of some water in an attempt to dilute. This will most likely mean your result will come back as diluted and you'll have to take it again. Many drug-free pee contests allow a retake on dilute results, some don't.

What about Rolaids and aspirin? Some people recommend taking a few Rolaids and aspirin a few hours before a drug test. Rolaids for specific gravity and aspirin to fool the test. They won't hurt, they may help, but are probably unneeded.

What about some random detox drink? I'm not saying they won't help, I'm saying they're a waste of money. They also will be unable to add creatinine to your system since you have to take said drinks right before a test. Those drinks attempt to dilute, but they are unable to do a proficient job as they (try to) accomplish what I've just explained to you but without the creatinine.

Marijuana drug screens look for 50 ng/ml of cannabinoids. If your test is positive then the test is sent to a lab which looks for 15 ng/ml of 9-THC-COOH.