Avatar universal

False Negative Drug Screen: Blood

Recently I have been given a blood drug test to make sure I have been taking my medication, MS-contin 15mg. I took it expecting to get some wierd questions about how much I had in my system(i took my last vicodin 5 because I was all out and felt like i was literally dying) and went to the docs. The test came back negative for ANY morphine at all.

This happened again to me when i was going for a job. Swab test came back negative which was wierd but why ask when it meant i got the job, right?

So I have an issue. They're taking me off and even worse accusing me of selling. The pain I suffer is around an 8 on a good day without meds (post-herptic neuralgia). WHY are my drug screens coming back with nothing?

What can I do to prove I'm taking them?
13 Responses
547368 tn?1440541785
Hello and Welcome to our Pain Management Forum. I'm glad you found us and took the time to post but I'm very sorry to hear about your situation.

You've asked a good question. I'm sorry I don't have a good answer. You and I know - as does your physician - that when you take opiates they show up in your UDS (Urinary Drug Screen) - yet yours didn't.

I do believe you - what reason do you have to be untruth to a group of strangers? What could it get you?

I can explain (to some degree) why different metabolites show up in a UDS than one might anticipate - I can't explain why one has a negative, or false UDS when they are taking opiates.

Human error does occur - not only in everyday life but in medical science also. That's the only explanation that explains your situation - at least to my knowledge. How can you prove it - or the fact you're taking your opiates? You can't.

Obviously your most pressing issue right now is how you'll manage your pain. It's unlikely you'll find a PMP will treat you but it may be worth a try. Make some calls - sadly your UDS results will haunt you.

Other members will stop by and offer their suggestions. Hopefully one of them will have better suggestions than I do. Hang in their my friend in pain and please let us know how you are doing.


Avatar universal
I'm sorry I'm late to your post!  :(  However, I join Tuck in welcoming you to our PM ( Pain Management ) Forum.  I'm so glad you found us!  

Unfortunately, I have small o good answer either as to why your meds wouldn't show up in your urine
Avatar universal

OOPS! I'm sorry but I accidentally hit post before I could correct and finish my answer to you. As you can see my "spell check" went crazy on my answer above.  :(   I realize you had a BLOOD Drug Test and not a urine test.  I have no answer for you as to why the blood test as well as the swab came back negative.  All of our bodies are so different!  As Tuck said, I, too, believe you.  There is no reason you would lie to a lot of strangers.  :)   Tuck is our CL (Community Leader) on this Forum and is extremely knowledgeable.  However, these drug tests that we have to take completely baffle us.  Please believe me when I say that we ALL are scared to death each time we take them.  We know we've taken our meds as directed but after all the horror stories we've heard of we can NEVER be sure what to expect the next time!  

I hope you will try to find another Pain Management Doctor that will be willing to give you a try.  However, I'm afraid, as is Tuck, that you will have a great deal of trouble finding one.  

You know there is 1 thing I just thot of you might ask your Dr. to resend your blood sample to a DIFFERENT lab or at the very least have it retested. They can ALWAYS make mistakes and in this case they definitely may have.

PLEASE stay in touch and let us know how you are doing.  We'll be looking for your updates.  I wish you the very best!
                                .............  Sherry  :)

Avatar universal
Update: Urine test came back positive all around for morphine. I'm going to hope this stupid test will make my doctor rethink their position on taking my meds away,
Avatar universal
I'm so happy that it came back positive.  May I ask which Dr. gave you the urine test?  If it was your PM Dr. that stopped your meds then what did he say before giving the test to you?  If it wasn't that Dr. then which Dr. did give you the test? OR the best scenario, was this a RE-TEST of the original Urine Test as we suggested above?  The reason I'm asking this is because so much rides on this.

I look forward to you update on this.  :)
Thinking of you......  Sherry  :)
547368 tn?1440541785
I hope this is great news!

When you say your UDS came back positive "all around" please explain what you mean. Where did you have the drug screen? I hope it was through the physician that prescribes your opiates.

It's important for you to know which UDS were used. The quick, cheap UDS called immunoassay are not very accurate. The more sophisticated UDS preformed by labs are much more accurate. Often a PMP office does the  immunoassay UDS first - to save money.

The immunoassay is performed first and is often used as a screening method. If the immunoassay produces results that are not expected an additional confirmatory GC-MS analysis is performed on a separate portion the biological sample.

The actual test, such as the GC-MS has an accuracy rate of 98-99% when performed perfectly - however this does not take into account that one uncontrollable factor - human error. It happens.

I think it's important to always know the type of UDS that is preformed when drug screening is done.

I hope this is great news. Please let us know.

My Best to You,
Avatar universal
My Urine test was performed by the lab with my PCP. She tested it for all drugs in my system and it came back 11,000ng of morphine(their threshold appears to be 50). I am going to have them fax this information to my Nuerologist/pain management doctor who has taken me off my meds and hope to discuss the potential of another test where they give me a pill and I sit and wait at the office taking blood every half hour.

I'm uncertain if this test will prove anything, my fear is that they will think I just took my meds for that one test and still remove me from my meds.

547368 tn?1440541785
Thanks for the update.

I'm out of town and ready to head home. I'll respond later.

Hang in there our friend in pain.

547368 tn?1440541785
Hi Again,

I am hopeful you will be able to influence your Neurologist - whom is also your Pain Management Physician (PMP). I must say that I haven't heard of a reversal once the decision was made to stop RX of opiates. I hope you are the first - indeed I hope that for all that have been down your road.

The "test" you want to request from your PMP would be very costly and time consuming. I haven't heard of that either - but I have hope for you.

The good news is it sounds like your PCP is behind you. If your PMP stands firm - you may be able to find another with the help of your PCP.

Please let us know how you are doing. I'll look forward to hearing from you.

Best of Luck,
Avatar universal
The result is as follows;

He believes I'm not selling or giving my meds. He believes I am taking them. HOWEVER; Given the nature of the opiod war in MA, he is unable to give opiates if the blood test comes back negative. He doesn't know why it happened and just needs to play it safe. If his license was not at risk he'd continue the medication program I was on.

He has now given me lyrica. Given what gabapentin has done, I'm not so hopeful. Its also massively expensive, almost prohibitively so.

Such is life, pain and waiting. I hope noone goes through what I had to, or what any of us did. I also hope his receptionist gets fired for her disrespect.
547368 tn?1440541785
Thanks for the update.

I'm so sorry this has happened. My heart goes out to you. I hear your story way to often here.

Gabapentin did nothing for me either. Lyrica has been much more effective than gabapentin - but not without the complements of an opiate.

I have read extensively for reasons and examples of false negative opiate screening. Most of what I read says the GC-MS is considered the gold standard and rarely is inaccurate. However how many PMP are actually utilizing the GC-MS. Sadly the word "rarely" is over looked.

I found this while searching:
"Concentration of a substrate in a sample is dependent upon a drug’s individualized absorption and metabolism rates as well as on the drug’s pharmacokinetics. Toxicology tests are designed with cutoff concentrations in mind; these cutoffs represent the lowest possible concentration that will produce a positive test result. These tests are calibrated to detect opiates taken within 1 to 3 days in the majority of individuals; however, individual variation that is based on metabolic genotype (eg, ultrafast metabolizers) should be considered."

No UDS is 100% accurate. There are lab errors and human errors and misinterpreted results. Sadly in PM those things are not considered. You are guilty, convicted without the benefit of doubt. We have no rights. No right to PM - it's considered a privilege - in my opinion we all have a right quality of life.

I'm waiting on that astute, go-getter attorney that finally takes a chronic pain patients case such as yours and wins. Only than will we have any rights. I may never see that day - but I keep hoping.

I wish you the best. Please keep in touch.

16134495 tn?1445567138
So sorry you are going through this, it is tough! I lost my insurance, hence my pain management doctor and went almost 3 yrs without meds and had no quality of life Thankfully got new insurance now.
     If your doctor is giving you a hard time even though he believes you, I would look for another doctor who has a spine and won't cave in to this new war on people with chronic pain!
Avatar universal
I'm SOOO SORRY!!!!  This is such a frightening environment that we are living in and I hate even thinking how much worse this atmosphere might become before things even hint at getting better.  I can't begin to imagine what it's like to get that type of news from your Doctor that you've trusted to help you for so long.  You have NO choice but to keep looking for another Doctor that will help you.  I URGE you to start looking.  You might ask your Doctor if he would recommend someone to you, since he does believe you.  Maybe even ask him for a note in your chart that states he BELIEVES YOU so that it's on record.  That way when.you take your records to a new Doctor they will see that he trusted you but do to their protocol at their practice he couldn't continue to give you the pain meds that you need and deserve!

We'll continue ue looking for your updates and HOPEFULLY,  they will be positive next time!  

Thinking of you.    ........     Sherry   :)
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