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Why is my urine test negative?

Mitsy

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Joined
Nov 10, 2025
Messages
2
I am prescribed Adderall for my ADHD. At my last med check my PCP ordered a urine sample, which came back negative for everything, including amphetamines. I take my prescription every day as prescribed. I don’t drink or take any other drugs I’m not prescribed. My PCP said it might be a lab error and asked me to come in to give another sample. Now I’m super nervous it’ll be negative again and I won’t get my meds refilled. Is this just a fluke with the lab? I’m not doing anything wrong, I’ve been taking Adderall daily so idk why it’s negative.
 
Tough to say --- once on a sub program I failed for morphine and hadn't taken any (or codeine etc). Couldn't really even argue ---idk say someone pulled a switcheroo but you don't switch clean piss out?
 
Not taking large doses of baking soda or anything that might alkalanize your urine, are you?

Change in urine ph can eliminate up to 99% of amphetamine and most of the other amine drugs of abuse, making them nearly undetectable in urine.
 
eliminate up 90% of amphetamine from your urine? I have certainly heard of playing with baking soda to adjust the PH of amph --- never anything about it eliminating or masking it from your urine however.

Source? (I will run a Google too in case this is info I just never heard) --- This is a lazy A.I overview

Ingesting baking soda to pass a urine analysis (UA) for amphetamines is a dangerous and unreliable method with no scientific evidence to support its effectiveness for this purpose.
  • It is not a reliable method: While some anecdotal claims suggest it may work by temporarily altering urine pH to reduce the elimination of amphetamines into the urine, there is no research to support this theory as a viable or safe way to pass a supervised drug test. Laboratories test for specific gravity, creatinine, and pH levels to detect dilution or adulteration, which will often result in an invalid or failed test.
  • It is highly dangerous: Ingesting large amounts of sodium bicarbonate can cause serious health complications, including severe electrolyte and acid/base imbalances, extreme diarrhea, and in some documented cases, gastric perforation (stomach rupture), which is a life-threatening medical emergency.
 
I am prescribed Adderall for my ADHD. At my last med check my PCP ordered a urine sample, which came back negative for everything, including amphetamines. I take my prescription every day as prescribed. I don’t drink or take any other drugs I’m not prescribed. My PCP said it might be a lab error and asked me to come in to give another sample. Now I’m super nervous it’ll be negative again and I won’t get my meds refilled. Is this just a fluke with the lab? I’m not doing anything wrong, I’ve been taking Adderall daily so idk why it’s negative.
Ok, if it is like some doctors offices, Notsmokeymcpot 42088 brings up a good point.

However the restroom( in one doctors office) it had a small metal door on the wall. You piss and put it in there. I saw 3 or 4 others in a box built into the wall.

Piss in the cup and with the top on; put it into there.

You open the door and put the cup with the cap( longish tube like thing built into the cap. If could easily be switched.

There is a chance someone panicked and didn't realize the short detectability of some drugs versus others.

Switched with a woman on purpose, why.
Am I the only one who sort of remembers The Cheech and Chong Movies?
This is a variable on that. A short line or two? in one movie about something similar. Put a parole or a probation officer. He had some of I think his.........piss.
---‐
Let's look at a more, subdued atmosphere, a doctors office.
----------
Situation to switch piss.( even clean)

Someguy, call him Tommy did a line of coke a 2-3 weeks ago. He is scared of losing his Zanax script.

He doesn't know that a simple urine test will not detect it( one line and a really short half life drug, for about 3-5 days( yes I looked it up) My guess was a week or so. Not a regular user.

Tommy's doctor: your urine test came up positive but....

Tommy: calm from the zanax but trying to not look nervous.

Doctor: It says you are, on 4 different drugs that I didn't prescribe you and that you are probably.... pregnant?

Tommy: WTF, I am not a chick and I can't even pronounce those drugs, let alone know what those drugs are except, I had hydrocodone in those Vikingden pills when I hads my wizzdumb teeths pulled,lol.

Tommy: I got stress man, not morning sickness. What the Fuck?

Doctor: cheap ass stupid lab( mumbling under his voice). Sternly his says go: Urinate into this cup.
( Next visit)
Doctor: well Tommy it says you are taking you script as prescribed except you did ask to take an extra pill twice and you, did.
Tommy: With ex-gf-troubles, and the legal system. That dog is mine. That bitch, can have her cat.
Doctor: yes I did, and all is well( He gets it, in his mind)( mubbling under his breath, at least he doesn't have alimony).
Tommy: gets his script.

THIS WAS BEFORE, HAIR TESTING. BESIDES, WHAT DOCTOR DOES THAT?
 
I
Not taking large doses of baking soda or anything that might alkalanize your urine, are you?

Change in urine ph can eliminate up to 99% of amphetamine and most of the other amine drugs of abuse, making them nearly undetectable in urine.
I take omeprazole, which is a proton pump inhibitor used to increase the pH of stomach acid. But it’s prescribed by my doctor and I’ve been on it for years and have always shown up positive for amphetamines when they test me so I wouldn’t expect that to be it.
They also check urine pH when they do the drug test. Mine was 7.7, which is within normal range (4.5-9)

Anyway she reordered the test and it came up positive this time (urine pH was 6.6 on the second test). I guess maybe the first one was a random false negative?
 
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Human error of somekind -- just be glad you weren't in rehab and it didn't show up positive instead of negative.

I could not even argue when it popped for morphine - who would believe me? Not me if I'm in the other chair......I'm sorry to say it but it is kind of refreshing to know it happens and it wasn't some kind of a stunt/test of character lol
 
Courtesy of GPT-5.2

At urine pH ~7.7 (mildly alkaline), ~75–90% of unchanged amphetamine is not excreted by the kidney over that period).

That’s a solid chunk of amphetamine being withheld from the drug test, and if your urine is slightly diluted, I’d say that’s a viable cause for a false negative.

But I’m no scientist
I

I take omeprazole, which is a proton pump inhibitor used to increase the pH of stomach acid. But it’s prescribed by my doctor and I’ve been on it for years and have always shown up positive for amphetamines when they test me so I wouldn’t expect that to be it.
They also check urine pH when they do the drug test. Mine was 7.7, which is within normal range (4.5-9)

Anyway she reordered the test and it came up positive this time (urine pH was 6.6 on the second test). I guess maybe the first one was a random false negative?
 
Not being an amphetamine guy I'm gunna say good enough for me to shut up.

If I was counting on that to work I would seriously look into it with Chatgpt being what it is. If that is true I am very amazed I never heard it before and thank you for the tip. Ill pass it along (To someone I don't care about as a guinea pig first) lol.

At like a sub clinic or something where a fail just means pay an extra 50 dollars --- I should lie and say than cover the tab...but I already won't like the person lol

I suppose buying one for Shopko for amph and testing someone that way would be cheaper -- someone do that for the sake of science!
 
eliminate up 90% of amphetamine from your urine? I have certainly heard of playing with baking soda to adjust the PH of amph --- never anything about it eliminating or masking it from your urine however.

Source? (I will run a Google too in case this is info I just never heard) --- This is a lazy A.I overview

Ingesting baking soda to pass a urine analysis (UA) for amphetamines is a dangerous and unreliable method with no scientific evidence to support its effectiveness for this purpose.
  • It is not a reliable method: While some anecdotal claims suggest it may work by temporarily altering urine pH to reduce the elimination of amphetamines into the urine, there is no research to support this theory as a viable or safe way to pass a supervised drug test. Laboratories test for specific gravity, creatinine, and pH levels to detect dilution or adulteration, which will often result in an invalid or failed test.
  • It is highly dangerous: Ingesting large amounts of sodium bicarbonate can cause serious health complications, including severe electrolyte and acid/base imbalances, extreme diarrhea, and in some documented cases, gastric perforation (stomach rupture), which is a life-threatening medical emergency.
You gotta massage the prompt, or the AI guardrails kick in and give you false information.

I’ve used this method several times to pass urine drug screens for methamphetamine and amphetamine. It’s not foolproof, but it’s effective.

Scihub these sources, they should both be on there:

“as little as 1% (of amphetamine and methamphetamine) may be excreted within 24 h at alkaline pH (8)” versus “as much as 70%” at low pH, implying an on-the-order-of ~99% relative reduction compared with strongly acidic conditions.

https://academic.oup.com/jat/article-abstract/22/6/481/781872?redirectedFrom=PDF

97% unchanged amphetamine estimated retained by the kidney tubules (only 3% excreted) in one large scale modeling study based on human data:


Lazy AI:

Could this cause false negatives?

Yes
—because many urine drug tests are concentration-threshold based, lowering urinary excretion can push a specimen below the cutoff even when use occurred, especially at low doses or later collection times.

In a controlled study of single oral d-amphetamine doses using a 1000 ng/mL immunoassay cutoff, only 19% of specimens after a 5 mg dose screened positive even without deliberate alkalinization, showing how easy it already is for low-dose exposure to miss that cutoff. (https://academic.oup.com/jat/article-abstract/22/6/481/781872?redirectedFrom=PDF)
 
I

I take omeprazole, which is a proton pump inhibitor used to increase the pH of stomach acid. But it’s prescribed by my doctor and I’ve been on it for years and have always shown up positive for amphetamines when they test me so I wouldn’t expect that to be it.
They also check urine pH when they do the drug test. Mine was 7.7, which is within normal range (4.5-9)

Anyway she reordered the test and it came up positive this time (urine pH was 6.6 on the second test). I guess maybe the first one was a random false negative?
If I had to guess, I’d say the alkalinity of your urine on The 7.7 test triggered a false negative.
 
Not being an amphetamine guy I'm gunna say good enough for me to shut up.

If I was counting on that to work I would seriously look into it with Chatgpt being what it is. If that is true I am very amazed I never heard it before and thank you for the tip. Ill pass it along (To someone I don't care about as a guinea pig first) lol.

At like a sub clinic or something where a fail just means pay an extra 50 dollars --- I should lie and say than cover the tab...but I already won't like the person lol

I suppose buying one for Shopko for amph and testing someone that way would be cheaper -- someone do that for the sake of science!
lol
It works for me when I’ve partied a little a day or two before the test, not when I’m using 8 balls on the regular. In that case, the amounts of meth in my urine are so high that even a.90-95% reduction in the drug leaves enough that it triggers the confirmatory cutoff on the test and I fail.
 
I am just amazed it isn't a well documented thing (here; apparently it is fairly well documented) as we all want to pass a drug test here and there. Maybe I just do not know the amph community well enough

Thanks for the tip.
 
Not being an amphetamine guy I'm gunna say good enough for me to shut up.

If I was counting on that to work I would seriously look into it with Chatgpt being what it is. If that is true I am very amazed I never heard it before and thank you for the tip. Ill pass it along (To someone I don't care about as a guinea pig first) lol.

At like a sub clinic or something where a fail just means pay an extra 50 dollars --- I should lie and say than cover the tab...but I already won't like the person lol

I suppose buying one for Shopko for amph and testing someone that way would be cheaper -- someone do that for the sake of science!
If I had a lot of money, and still drank; I would be interested in that idea, for science and for money.

That info and other experiments that produce false positives.( we all know about poppy seed bagels, ( not talking to you, but the lurkers who think they know something we all do)

Seriously, if there was serious testing into false positives; and it could be shown throughout a range of substances: There would at least a book deal.

Also as a side note; this info could be very valuable to lawsuit lawyers. Get fired for a false positive and prove there test is flawed. $$$$$$$$
Better yet, have the plaintiff, testify( if it is true, and you can prove it)

Especially if a client really really does nothing that would cause a legal firing(never does drugs)

If they had long hair; have 5-20 labs test it.
It will show all, he or she; did or didn't do drug wise in the last year.

Get a judge to allow it into evidence. If this person has done nothing in the last year; throw in the false positive research, and Big Time settlement.$$$$$$$$
Also depends on occupation.

In Michigan, you would unfortunately make the Law offices, of Sam Bernstein, Mike Morse, and of course Geoffrey Fieger law offices( Geoffery is in bad health right now; but I bet a shit load of money might change that)lol

Side note, his dead brother Doug was the lead singer of band: The Knack: My Sharona( one hit wonder); don't get that song stuck in your head.

It is about his crush on a 17 year old girl. He was 25. Legal in Michigan, but hell no. Age of consent isn't the issue. Creepy and gross, is an understatement.

A Grown man and a song about his crush on a 17 year old girl. No, that is wrong.
 
^ Oh damn I did not know guy was from MI or that song was about a minor. Thank you for the coffee table trivia knowledge!

False positives certainly would be a real bad look. I almost believe I MUST HAVE consumed some morphine unwittingly? (Sounds impossible and IS implausible).

Than again the switcharoo is just as likely

I actually do not condone anyone testing this theory due to the whole "Stomach rupture" possibility --- I mean if you are facing 20 yrs or some shit make your own choice -- but just for the sake of doing it....

Well it'd be cool if someone did but I can't ask for volunteers in good faith
 
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