This is what I know about passing piss test for weed:
1)
THC metabolites are stored in fat cells; thus the less fat your retain on your body, the better chance of passing you will have.
2)
Exercise daily to prevent the build up of THC metabolites in your fat cells and fat. Don't be a pussy about it either... Break a serious sweat during your workout of 30 - 45 minutes daily. I'm a weight lifter and boxer and my workouts run 1.5 to 2 hours sometimes. I have no sympathy for couch potatoes
3)
Take Niacin daily!! because it lowers cholesterol and fat in your blood stream which contributes to weight loss. HOWEVER, do not take niacin on an empty stomach and drink lots of water. in fact, you should increase your water intake significantly as a measure of promoting better health and hydration anyways. Niacin can be bad for you if too much is taken at once or without enough food or water in your system.
This is important: niacin is used to pull the cholesterol and fat out of your blood stream. So, does it help you not gain weight and not retain fat? The answer is a resounding yes. Niacin combined with regular exercise promotes leanness and lower cholesterol. Always take with food and water. I take two 500mg pills in the morning with breakfast and 1 before my workout and 1 before dinner. Niacin helps me wake up and start the day alert and full of energy. Niacin supercharges my workout and makes me strong. I also sweat significantly more on niacin so weight loss is increased. Niacin is a wonderful drug if used correctly. fuck the naysayers, because I know it helps.
4)
This is more of a lifestyle change, than something you can do right before a test to pass. taking a huge dose of niacin before a test is harmful to your health. Here is another fact. If you are fat, you are more likely to fail a piss test for weed than if you are skinny, even with water loading. Just trust me on that. Skinny folks have the advantage here and that is all there is to it.
5)
On the day of the test, and assuming you have changed your lifestyle to be inline with the previous suggestions, do drink a lot of water. I have passed many piss test simply because I loaded up on water. However, the water loading does do several things. Water loading lowers levels of chemicals normally found in urine and it makes your piss look like water. Depending on the test used (if gas spectroscopy is used) this will be detected. If the test is just a piss test in a cup, like many labs use, dilution will go unnoticed and you will pass more than likely. Take a super B complex and multivitamin 1.5 hours before your test in conjunction with lots of water and possibly a diuretic like cranberry pills sold in the pharmacy to help old farts piss better. Important: wait until you see yellow from the vitamin to go piss. Pee a lot before the test; not just once or twice like 4 or 5 times. In fact, your bladder should be straining a little before that test. That means that water is simply being passed for urine instead of re-circulated by the kidneys to remove impurities. On a normal day, your kidneys will recirculate water specifically in order to clean out waste with each pass, this is why piss can be extremely yellow or only slightly yellow depending on your consumption.
-if gas spec is used you may be fucked no matter what, if using your own piss. gas spec is way more sensitive then other test. Dilution may not help at all.
-if piss test in a cup is used, you will more than likely pass. Those test have a threshold where below that threshold, nothing is detected so dilution works well here.
6)
Fake piss can be detected. Fake piss is missing the male and female hormones excreted in real urine. Gas spec will reveal the absence of these hormones. Piss test in a cup does not care about hormones. Hope and pray, they are not sending the piss to a real lab that employs gas spec.
7)
Detox drinks are a sham. however, Diuretics which make you piss more will increase the volume of urine you flow and can be used in conjunction with water loading, vitamins and creatine supplement.
the best option: use the wizzinator or similar device and substitute (carefully) the fake piss with clean urine from a person of the same sex. 1) you are not using your piss, you are using someone's who is known to be clean. 2) this method defeats both kinds of test; gas spec and piss test in a cup. Be careful to maintain the piss between 95 and 98 degrees. I have heard anecdotes about overheating on the IV bags used to hold the piss. If using someone else's piss, put it into a sterile container and refrigerate up until you are ready to use it. Piss can go bad, yep that's right piss goes bad just like milk does if left and room temp for too long.
This is the best of my cumulative knowledge. I have passed and failed test. I have learned from experience. If you want to argue with me, knock yourself out.