Opiates (OPI)

CPT Code: 

80101 

Specimen

Urine 

Volume

20 mL 

Container

Use plastic urine drug bottle and evidence tape or tamper-evident container for forensic specimen. Collection kits are available by request from the laboratory. 

Collection

Urine specimens should be collected in clean, unbreakable, and leak proof containers.  Freshly voided urine specimens should be used.

Fresh urine specimens do not require any special pretreatment.  No additives or preservatives are required.  Boric acid should not be used as a preservative.

Specimens may be encountered that display turbidity.  It is recommended that such specimens be centrifuged before analysis.

Specimens should be within the pH range of 5-8.  Specimens with a pH outside this range should be adjusted to this range by the addition of 1N HCl or 1N NaOH before analysis.

Specimens should be at a temperature of 20-25 ⁰C before analysis.

Stability: 

If not analyzed immediately, specimens should be stored refrigerated for less than 24 hours.  Specimens should be frozen if storage longer than 24 hours is required.

Cutoff

2000 ng/mL

Note: This method provides only a preliminary analytical test result.  A more specific alternate chemical method must be used in order to obtain a confirmed analytical result.  Gas chromatography/mass spectrometry (GC/MS) is the preferred confirmatory method.  Other chemical confirmation methods are available.  Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are used.

Use

Measurements obtained with OPI method are used in the diagnosis and treatment of opiates use or overdose.

Information: 

Opiates are a class of compounds that includes morphine, codeine, and heroin.  Morphine and codeine are naturally occurring alkaloids that are found in opium, a substance exuded from the unripe seed pod of the opium poppy Papaver somniferum.  Heroin is a semisynthetic derivative of morphine.

Morphine is a potent analgesic.  Codeine is used in analgesic preparations and as a cough suppressant.  Heroin is an even more potent analgesic than morphine.  Both morphine and codeine are legitimate drugs.  Heroin is a drug of abuse that may be snorted, smoked, or dissolved and injected subcutaneously or intravenously.

Opiates are absorbed rapidly.  Heroin is converted almost immediately to morphine, which is excreted in urine both unchanged and as a flucuronidated metabolite.  Excretion takes place over a period of a couple of days.  Codeine is excreted in urine as a glucuronidated conjugate, as free and conjugated norcodeine, and as morphine.  The presence of opiates in the urine indicates the use of heroin, morphine, and/or codeine.

6-Acetylmorphine (6-AM) is a metabolite of heroin; its presence is positive proof of heroin use.  6-AM has a very short half-life (ie, it is detectable for only a few hours after heroin use).  Current literature shows that 10 ng/mL is the lowest testing level by GC/MS that can reasonably be used to consistently and accurately identify and quantitate the presence of 6-AM.

Methodology

EMIT®