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    Chaoku's Avatar
    Chaoku Posts: 2, Reputation: 1
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    #1

    Sep 21, 2012, 07:30 PM
    False Negative Hair Test?
    Here's an interesting question. I may have to submit to a hair test for a Job I'm currently in the process of applying for. I was afraid of a single usage of pot showing up from a couple months ago. So I bought a hair test from Hairconfirm and sent them a sample to test. I received the results and it came back negative. Fantastic.

    But I take 20mg of an Adderall generic everyday, and that didn't show up either. Is it possible that a dosage of 20mg of Amphetamine salts a day is not enough to accumulate in the hair, to cause a positive result on a hair test? Or was this a mistake by the lab?

    Ive spent hours of time researching hair tests and how certain drugs are incorporated into the hair. I realize now that a single use of Marijuana will almost never show up in a hair test. But amphetamine is supposed to actually be attracted to Keratin and readily bond with hair. Any info would be greatly appreciated.
    DrBill100's Avatar
    DrBill100 Posts: 3,241, Reputation: 502
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    #2

    Sep 22, 2012, 08:32 AM
    Amphetamines have a greater incorporation into hair than THC/THCA. This is generally attributed to an affinity for eumelanin but also involves route of incorporation (how does the drug get into the hair).

    Low and infrequent use of cannabis is almost never detected in hair testing and the metabolites do not bind or associate with eumelanin and are not deposited directly by circulation.

    Other base drugs (including amphetamines) are deposited in a dose dependent manner and supposedly at least in part directly from circulation but are also influenced by many factors that relate to personal hair growth and properties.

    With HDT false negatives are the rule and not the exception. While the medium may be effective for detecting heavy drug use it is ineffective at detecting low and infrequent use of most drugs (with very few exceptions). It is accepted that “Positive results from hair testing are generally expected only when a person has used a drug at least four to six times per month” (Galanter & Kleber)

    Failure to detect the cannabis use you mention is to be expected. Failure to detect the AMP can probably be explained by age, hair color, dose and number of other factors. I doubt that it was error but would probably occur on future tests as well.

    Nakahara, Y (1999) Hair analysis for abused and therapeutic drugs. Journal of Chromatography B, 733 (1999) 161–180, [p 174 contains graph of incorporation by drug type]

    Galanter & Kleber, 2011 Psychotherapy for the Treatment of Substance Abuse, American Psychiatric Publishing, Wash, DC, p. 58
    Chaoku's Avatar
    Chaoku Posts: 2, Reputation: 1
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    #3

    Sep 22, 2012, 09:22 PM
    Thank you for your response, DrBill.

    My hair is very fine in texture. And I started balding on the crown of my head at 19 (im 23 now.)

    I wonder as well if my recent weight loss might be a factor. Since starting my adderall, I have lost weight consistently at about 2.5lbs a week. (I did not start adderall to lose weight for all you people out there that think it's a miracle diet pill. Im still hungry, but it does curb the appetite. Especially when you are focused and occupied on something else. I take adderall because it focuses the spiraling, swirling thoughts my mind was having such a hard time finding order in. Like a TV flashing through channels. Adderall helps me stop on the channels/thoughts I want to stop on. Instead of losing track of the channel/thought I was trying to focus on.)

    Tangent aside, I wonder if the detox my body has gone through from weight loss, along with genetically pre-disposed thin hair, both in quantity and quality, could cause low Amphetamine readings.

    I also read on some forums, people using Salicylic Acid, found in certain shampoos, to strip the hair of drugs and drug metabolites. I know that these surface treatments wouldn't affect the core of the hair, where most of the drug(s) would reside. But I have used Dermarest Psoriasis shampoo (whose active ingredient is Salicylic Acid) for a couple years because of dermatitis of the scalp.(which, now that I think of it, may also be another reason. Since the oils on my scalp--another method of drug infusion into hair?-- may be reduced by the dry scaly dermatitis.) Coupled with my thin hair, could the Salicylic Acid be more effective? Because the hair diameter is small enough to permit the surface treatment reaching into the hair cortex?

    I know I'm stretching to make connections. And this is all speculation. But it seems amazing to me that with the seemingly endless praise of hair testing for drugs, as an unbeatable test, that so many factors (and natural or incidental a that, rather than purposeful) could possibly influence not only the detection of a drug in the hair, but the actual uptake of the drug into the hair as well.

    Thanks so much, DrBill, for your input. Its hard to find an unbiased scientific answer about hair testing questions on the internet. And nothing has put me at ease more then the responses and discussion I have read on your answers and posts. So, again, thank you for your help.
    DrBill100's Avatar
    DrBill100 Posts: 3,241, Reputation: 502
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    #4

    Sep 23, 2012, 07:07 AM
    My hair is very fine in texture. And I started balding on the crown of my head at 19 (im 23 now.)

    I wonder as well if my recent weight loss might be a factor.
    Hair drug testing (HDT) is dependent on structure (fine) and color (eumelanin content). Growth is also hormonally controlled. So that probably describes why the AMP was not detected.

    As to the THC, that is not influenced by eumelanin nor does it enter hair via the same route(s). HDT is simply not an effective method for detecting low level cannabis use and has a very high failure rate (40%) in detecting even heavy use.
    Dance14's Avatar
    Dance14 Posts: 23, Reputation: 1
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    #5

    Nov 15, 2012, 07:55 AM
    Quote Originally Posted by DrBill100 View Post
    Hair drug testing (HDT) is dependent on structure (fine) and color (eumelanin content). Growth is also hormonally controlled. So that probably describes why the AMP was not detected.

    As to the THC, that is not influenced by eumelanin nor does it enter hair via the same route(s). HDT is simply not an effective method for detecting low level cannabis use and has a very high failure rate (40%) in detecting even heavy use.

    Dr bill. Does alchoal shown up in a hair test?

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