Iowa Methodist Medical Center

Drug Screening

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Tests available  Drug Screen, Limited, Urine

 Drug Screen, Urine,

Monitoring

Sympathomimetic Amines (Amphetamine/ Methamphetamine)

X X

Ecstasy (MDMA,MDA,MDEA) X X

Barbiturates X X

Benzodiazepines X X

Cocaine X X

Opiates X X

Oxycodone (OxyContin, Percocet) X X

6-AM (Heroin) X X

PCP X X

Marijuana X X

Methadone X X

Propoxyphene X  

Other   Fentanyl, Buprenorphine and Tramadol sent to MedTox

IMMC Drug Screening

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Screening cut offs

  Screening cut off (ng/mL)Sympathomimetic Amines (Amphetamine/

Methamphetamine)300

Ecstasy (MDMA,MDA,MDEA) 500Barbiturates 200

Benzodiazepines 200Cocaine 150Opiates 300

Oxycodone (OxyContin, Percocet) 300

6-AM (Heroin) 10PCP 25

Marijuana 20Methadone 300

Propoxyphene 300

IMMC Drug Screening

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Confirmation Testing  Confirmation testing

performed automatically at IMMC

Confirmation testing available upon request (Sent to MedTox

Laboratory)

Sympathomimetic Amines (Amphetamine/ Methamphetamine)

X  

Ecstasy (MDMA,MDA,MDEA)   X

Barbiturates X  Benzodiazepines   X

Cocaine X  Opiates   X

Oxycodone (OxyContin, Percocet)   X

6-AM (Heroin)   XPCP X  

Marijuana X  Methadone   X

Propoxyphene   X

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Drug Screen, Prescription/OTC, Urine

• Performed at MedTox Laboratory• Detection and identification of prescription

or over the counter drugs frequently found in drug overdose or used with a suicidal intent. This test is designed to qualitatively identify drugs present in the specimen

IMMC Drug Screening

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Other individually orderable tests of

interest

• Methylphenidate (Ritalin®), • Adderall • Almost any Benzo you can think of…

IMMC Drug Screening

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Possible causes for false positive and negative results

Screening Assay Commonly Detects False Negatives False Positives

Sympathomimetic Amines

(Amphetamine/ Methamphetamine)

Amphetamine, Methamphetamine

PseudoephedrinePhentermineEphedrinel-Amphetaminel-Methamphetamine

Ranitidine 

Ecstasy MDMA,MDA,MDEA N/A DiphenhydramineBuproprionTrazodone

Barbiturates AmobarbitalButalbitalPentobarbitalPhenobarbitalSecobarbital

BarbitalHexobarbital MephobarbitalMetharbital

N/A

Benzodiazepines DiazepamNordiazepamOxazepamTemazepam

AlprazolamClonazepamLorazepam

Oxaprozin

IMMC Drug Screening

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Possible causes for false positive and negative results

IMMC Drug Screening

Screening Assay Commonly Detects

False Negatives False Positives

Cocaine Benzoylecgonine CocaineEcgonine Methyl EsterCocaethyleneEcgonine

N/A

Opiates MorphineCodeineHydrocodoneHydromorphone

OxycodoneOxymorphone 

LevofloxacinOfloxacinOxycodone

Oxycodone OxymorphoneNoroxycodoneOxycodone

N/A N/A

6-Acetylmorphine 6AM N/A Morphine Codeine Methadone

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Possible causes for false positive and negative results

IMMC Drug Screening

Screening Assay Commonly Detects

False Negatives

False Positives

PCP  PCP N/A DextromethorphanMarijuana Delta 9

Carboxy THCN/A Marinol

Niflumic AcidMethadone EDDP Methadone

EDMPN/A

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DRI® Opiate Cross-Reactivity Tables

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• And many, many more

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DRI® Benzodiazepine Cross-Reactivity Tables

IMMC Drug Screening

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What does a “positive” urine drug test result on an immunoassay actually mean?

• the patient was compliant and took the prescribed drug as directed.

• the patient was only partially compliant and just took 1 dose prior to collection.

• the patient could have directly spiked/added the drug into the urine sample after collection.

• the patient took another medication that cross-reacted with the immunoassay causing a false-positive result.

False-positive results are one of the limitations of using an immunoassay.

IMMC Drug Screening

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What does a “negative” urine drug test result on an immunoassay really mean?

• the patient is not compliant with their prescribed medication• the patient was partially compliant and maybe missed a few doses,

or took less medication. • the patient is well hydrated and the urine is dilute or possibly

adulterated. • the wrong test might have been ordered and the test may not cross-

react with the patient’s medications. • the drug may actually be present, but it is below the cutoff or

detection limit of the assay leading to a false-negative result.

False-negative results can happen as easily as a false-positive result with immunoassays. Therefore, it is important to look at the assay cutoff or detection limit when interpreting test results.

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Other information of value

• timing between when the patient last took their medication and when the urine sample was collected.  

• Specimen validity testing can also be used to help determine the integrity and quality of the patient’s sample.

IMMC Drug Screening