Ask Old Hippie: Will Cranberry Juice Help You Pass A Drug Test?

Dear Old Hippie: I have heard that in many cases you can flush your system with cranberry juice. Is this true?

I am eligible for a medicinal marijuana card in Ontario, but before I had the diagnoses that helped me and made it so I was eligible, I consumed cannabis on occasion to deal with my massive PTSD and other emotional disorders, when I returned from an intense situation out of the country. Before that I had not smoked at all. With the added pressure from being arrested because of my breakdown, I found it was the best fix for my emotions. I was always wary that my newly restarted consumption after ten years of not smoking could get me in trouble. So for others in my situation, and for just my own personal knowledge, does cranberry juice help or do any of the alternatives sold online?

Dear CK: Well, I’m glad someone finally asked me this question, because there’s just so much BS floating around the Internet about this subject, and I’ve been looking for an excuse to put some good information out there. Drug testing is a $6 billion business in the United States alone, and it’s used as an excuse to keep a lot of productive, creative people out of the workforce or in jail.

The simple fact is that the basic urine test does not actually test for THC. What they actually look for are metabolites — substances created by the body after you ingest cannabis — and those metabolites are stored in your body fat for a relatively long time: a week or so for occasional users, up to a month for regular users, and anywhere up to three months for patients like me who take their medicine several times a day, especially in edible form.

So the first rule of understanding the urine test process is that time is your friend…the longer you can delay the test after your last toke, the more chance you’ll have of testing negative. So the obvious, first, and most important thing is to stop smoking or using cannabis in any way as soon as you find out you’ll have to take the test, until your test results come back negative.

Some people recommend “adulterants” such as bleach, eye drops, Mountain Dew (really!) or even commercial products on the theory that these will “clean” or “mask” the results somehow. This is merely wishful thinking. But now labs have begun to test for these things as well, so using them might actually make you look worse for attempting to beat the test willfully.

Now we’ll get into the deepest area of urban legend: the idea that some magic drink or pill will “flush” the metabolites out of your body. This belief has caused untold people to fail tests, but worse, caused them to go through some serious shit on the way, and in the case of the recently-popular colon cleansing products, I mean that literally.

There is absolutely nothing you can eat or drink that will, by itself, insure you pass a urine test while a detectable level of THC metabolites is still in your body. Period.

The good news is that it is possible to beat a urine test. If your marijuana use is rare or occasional, or if you’re near the middle to end of the detectable period for your level of use or you’re not a heavy user, you have an excellent chance with the dilution method, which I will describe in detail below. But first: substitution.

The Substitute Method

The only absolutely sure way to pass a urine test is to go in there with clean human (or synthetic urine, in most cases) at the correct temperature. Even this will not work for high-security or probation urine tests where they actually watch you pee, unless you come equipped with an insanely realistic ninja pee kit, and you better do a lot of practicing beforehand.

While I’ve been assured by an employee at a drug testing lab (who shall obviously remain nameless) that they don’t or can’t check whether the urine came from another individual of the same sex, they will detect prescription drugs used by that other person. If your friend doesn’t smoke weed and gives you her pee, she may be doing you a favor, but if she happens to legally be taking something they also test for (such as antidepressants or anti-anxiety pills), you’ll be expected to show them a similar prescription in your own name as well…and with the same dosage. So be sure to ask your friend about everything!

The thing about urine testing is they now look at the color, the temperature, and some of the basic physical characteristics (such as pH) to make sure it’s really urine they’re dealing with, and not Mountain Dew. So whatever you bring them has to be close. And pee goes bad, so you can’t keep it in the back of a drawer. You can keep it in the refrigerator up to a week, or freeze it for a year or perhaps longer, but you can’t keep it in little plastic baggies.

So here’s what you do. Go down to your local big pharmacy or supermarket and get some 2 ounce travel bottles, which people use to repackage liquids before getting on an airplane. It turns out that they allow 2 ounces of liquid on planes, and 2 ounces of urine happens to be the standard amount for drug tests as well. These containers should ideally have screw-on caps that can’t flip open, and flattish ones are better (you’ll see why soon).

Put the urine into the container. If you can get your friend to pee enough, you can fill up a few of these, so you can freeze them in advance (if the test is this week, don’t freeze it at all, just keep it in the refrigerator). When freezing these containers, you should leave the top open so there’s no pressure buildup, and obviously keep them upright and away from any food. Once they’re frozen solid, close the top and mark with the date and the word “pee” in big letters so you don’t make a terrible culinary mistake down the road.

When you know you’ll need it, simply put the container in the refrigerator at least 24 hours before the test to defrost. Before you leave your house to take the test (give yourself at least 45 minutes if possible), open or loosen the top to allow pressure to escape, and put the container in the microwave for 10 seconds, which gets it up to approximate temperature. Then close the top (rather important!) and carefully put it in your underwear (guys, you can’t wear boxers for this) tightly next to your body where it won’t show but it will pick up your body heat. Preferably in front, eh?

At the lab, they will make you empty your pockets, but they won’t be sticking their hands into your underwear, so when you go into the bathroom, empty the bottle as silently as possible into the cup (while making as much other masking noise as possible, like coughing), and then you must pee into the toilet audibly, because they will expect to hear these kinds of noises. Personally, I would pee a bit into the cup if I was using synthetic urine, because that might help stop them being able to detect the synthetic that way…and even with “dirty” urine, you’d only put maybe 1/4 ounce or so extra in, so it would be automatically diluted by 8 or 10 times. You’d have to be Snoop Lion to fail that one! :-)

The Dilution Method

The dilution method works on the principle that they’re looking for a specific level of metabolites in your urine, which is generally 50 ng./ml. If you can dilute your urine so the level is lower than that, you pass. Simple, but the labs figured that out long ago too, so now they check for too-dilute urine by looking at the color, and they also test for other stuff to attempt to make sure it’s real, undiluted urine. Drinking water will not “flush the THC out”, but it will dilute your urine. So after putting together every bit of up-to-date information I can find, here’s what I would do:

1. If you have at least 3 days before the test, exercise a lot each day (not so much that you invite heart attack or collapse…use your common sense here!), both cardio and muscle-type exercises. This will help your body burn off fat, which may have some stored THC or metabolites. But this will also recirculate those things into your bloodstream, which is why you should stop exercising 48 hours before the test.

2. Three days before the test, start eating red meat or taking creatine (available at places like GNC). This will build up the creatinine levels in your system, because they test for this substance (a metabolite of creatine, found in meat) to make sure your urine isn’t diluted. If you don’t take this step, you’re likely to fail the test right here, so if you don’t have time to prepare, your only safe hope is clean urine.

3. At the same time, you should start drinking a natural diuretic that will help toxins and other foreign substances move out of your body through urine…something like…cranberry juice! See, there’s always a hint of truth in every urban legend! Here’s where cranberry juice fits in, and it can really help, but you have to do the other stuff too. Other mild diuretic drinks will work too, like tea and apple cider vinegar.

4. The latest trick I’ve found is to take zinc sulfate (not any other kind of zinc) pills, which you should be able to find in health food stores or GNC. This not only helps block detection of THC, but also cocaine and methamphetamine, and the drug testing folks are pretty worried about it, so you know that’s a good thing. I would take one or two pills (usually around 200 mg. each) four to six hours before the expected time of the test, or the night before if the test is first thing in the morning.

5. The hardest part here is next. An hour or two before the test, take some B vitamins to color your urine (50 to 100 mg. of B2 or B12 or B-complex is generally recommended) and then start drinking water like crazy, a glass every 15 minutes or so. You should drink a total of about a quart of water. Please do not overdo this part, because you can actually die from water intoxication, though you’d have to drink a lot more than that (yes, that means that cannabis is actually safer than water). You should also urinate at least once during this time (whew!), because you should not give them the first urine sample of the day for testing.

6. When it comes time to give the sample, take it “midstream”, so to speak…first pee into the toilet, then into the jar. This will give you the best chance of the lowest concentration of metabolites.

Sometimes after all this preparation, your urine will still come off as too dilute, and they generally give you a second chance to take the test. Schedule that out as far as possible (tell them you have a prepaid vacation or something) and next time…don’t dilute quite so much and you should be fine. Good luck!

Here is Erowid’s master page on drug testing, if you have enough interest to get through it all.

Got a question for Old Hippie? Just post a comment below, or use the contact form.

Revision 1.1 – 20 March 2013

Superstore 468x60 Ask Old Hippie: Will Cranberry Juice Help You Pass A Drug Test? Old Hippie is a father of two boys and thankfully living in California where all this kind of thing is legal. He started smoking marijuana in 1967 in high school, experimented with mind-expanding drugs of all kinds, and then straightened out 15 or so years later to become an airplane pilot. After being diagnosed with depression in 2000, he lost his job and most of the following decade to prescription medications (such as antidepressants) which sapped his energy and will. Finally, a chance conversation with a friend led to a doctor’s recommendation for medical marijuana (MMJ). This changed his entire life, health, and outlook for the better. is his continuing story. It’s also his way to provide experienced advice on using medical marijuana effectively and responsibly, as well as advocacy, activism, and support for others. Old Hippie teaches about safe use of cannabis edibles, Canna Caps, vaporizers, dosing, and even microdosing.

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  1. loveings11 said:

    ok so i dont smoke much at all i mean like once in a blue moon. but this weekend i smoked all weekend and now have to piss in a week or so. Now if i drink water and cranbarry juice and eat right for the week and than take a vitamen pill befor the test will this work for me to pass the test. I know i shouldnt of smoked in the fist place but i did and now im here askin how i can get clean for this test. please let me know the best thing to do asap

    • shankninja said:

      Just follow his advice and buy a test kit beforehand if you want to be sure it’s clean, or substitute

  2. Anonymous said:

    The erowid link in the zinc sulfate section says that zinc sulfate does NOT work, which is the opposite of what your article says.

  3. Anonymous said:

    I know that it’s impossible for you to tell me if I would pass a drug test or not, even if I laid out all the details for you, but I have a question for you:

    I have a urine test that has to be completed within four days at most. It’s been about a week now since I last smoked, and I am nowhere near a regular user. Over this last week I’ve been to the gym twice, where I’ve had rather strenuous workouts (I was unaware of the drug test until just about ten hours ago, so this was just something that happened). I’m still super worried about being able to pass the test, though. I know that the substitution method will work, because I can just get my sister to give me some of her urine, but I was curious if one of those home drug test kits that you can buy at places like Target are anything to go off of? Because I could easily pick up one of those and test myself. I can also get on the dilution method if needed. Or should I just go look for a travel container and go the sub method? I’m just super worried about the urine being the right temperature, because if I use a travel container I can’t use a hand warmer to make sure it stays warm…

    Anyway, thanks for your time, and I’ll hope to hear back from you soon!

  4. Anonymous said:

    i was a recent user until about 2 weeks ago. my intake was very low (a couple of small bonk hits each night for maybe 2 weeks).
    i have not smoked in at least 2 weeks and will likely be tested next week or the following.

    how do you think i’m looking?

      • Anonymous said:

        I have a probation test coming up in 12 days I last smoked last night. I shared 3 bowls with my friend and hit the bong once earlier that day. I was a frequent smoker until my Probo started almost 3 months ago but then I got clean. In the past 2 weeks I’ve smoked 4 times (2 hits usually). Keep in mind I was clean before deciding to do it again. I know it was a would decision on my part but I figured worst case senario I’d buy a kit at gnc and then test myself shortly before my actually test to ensure I pass. What can I do to make sure I will pass? I’m 120 lbs have a great metabolism and am startin ski practices this week which will get me sweating and exercising. Do the gnc detox kits actually work?

  5. aaron said:

    i did less than a gram of coke on saturday at midnight since the use ive drank 3 gallons of water ran 2 miles went to the gym for 2 hours on sunday and monday and drink 36 fluid oz of cranberry juice will i be good for tuesdays test at 11am

  6. Anonymous said:

    I was smoking atleast 3-4 joints a day for the past few years. I quit smoking about a week ago. Do you think I can use the dilute method or go with substitution? It’s a pre employment test, so they can’t sit there and watch me.

  7. Becka said:

    I’ve been clean 6 months from smoking but i just recently smoke on the 14th, i found out i have to do a UA in 2 days how do i clean out my system?

  8. max said:

    I am 6′ 0″ 140 pounds i smoked on thursday and barely friday i was using pretty regularly too, My school might drug test me on monday, it’ll probably be one of the home tests you buy from walgreens, is there anything i can do? please help!!

    • Old Hippie said:

      Home tests are easy to beat if they don’t watch you, just have a small container of water and dilute enough that it’s still yellow. Don’t try to use the sink because they’ll hear it.

  9. neicy said:

    I smoke everyday….I personally have to pass a UA,, you think I can do it?

  10. Jacob said:

    I have a drug test in about 9 days. I’m usually just a weekend smoker (usually 1 bowl a day on Fridays and Saturdays.) I last used on March 27th, 1 or 1.5 bowls. I’ve been exercising and drinking water and cranberry juice since the 28th. If I follow the dilution method you posted, should I be able to pass my drug test? Love your articles by the way.

  11. the man said:

    Ive been clean for 45 days and before that was smoking weed all day everyday for 10 years like 3gs a day I have a test coming up on the 13th of april will i pass?

      • the man said:

        So using ultra mask should work, it says for couple times a week users to quit 3 days before test, I quit 53 days before test I’m hoping this works!!!!

  12. WorriedGirl23 said:

    HELP!! I have read every Cannabis forum, every credible article, and asked every head I’ve ever met how to pass an upcoming, pre-employment UA. I must say, your article was MOST helpful but I would love to be more specific and ask you for some advice about myself for the most honest answers. I am a healthy, 23 year old female. I am around 5’2 115lbs. and I have been a regular user for several years since my last clean-up period. It is usually mid-grade bud or so but after visiting Colorado the beginning of this month I partook in some great bud and a few edibles. I plan on following every detail of your dilution method as I am wary of any substitutions (I don’t even know where I’d find a clean friend and warming synthetics are very tricky- too much for me!). I am drinking at least a half gallon of water everyday to continue the dilution process, as well as purchased a rather large detox from GNC (QCarbs something or another) to use the week of the test. Thursday I am having a foot-detox done at my local spa, and exercising everyday until the week of. I’ve quit smoking since I found out, almost a week ago. I also took a week “vacation” in order to buy myself some more time from now until the UA. So realistically I have about another week and a half, to two weeks until the test. With all of this information, do you have any other personal suggestions for me, or do you even foresee me passing altogether? Thank so much and wish me luck!

    • Old Hippie said:

      Regular users have the hardest time. My wife uses tiny doses like me and once tried a month off, and was still testing positive after that. So if you’re very active with low body fat you have a chance. Burning off the fat by safe but sustained exercise is your best shot right now, not wacky detox methods. The dilution in the last 24 hours is what will make the final difference. Good luck!

      • Anonymous said:

        You are awesome! Thanks so much for the timely response, I truly appreciate it! As you’d say, nugs and hugs!! Even though this is something we should NOT EVER have to worry about in this community, at least we have people like you to count on!

  13. M.b said:

    I hav e a test monday morning, and I’ve last smoke this wednesday. Should I try using your dilution method or this detox method: ?? I have creatine and vitmin B, so I can do any. Thanks

    • Old Hippie said:

      From what I can tell, the author of that article is actually doing essentially the same thing as my dilution method, except focusing on the drink itself and calling it “detox”. So best of luck whichever one you use!

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