Workforce Screening Mena

Parkway Clinical Laboratories PCL is a United States based, College of American Pathologists CAP accredited, CLIA certified, full service specialty toxicology laboratory. PCL has been a trusted partner in delivering in-vitro diagnostic services for more than four decades. We are a global provider of addiction screening and opioid prescription monitoring service focused on facilitating a drug free workplace.

Located outside Philadelphia, Pennsylvania, with a branch office in Dubai Healthcare City, Pcl is fully equipped to perform the following tests:

  • Semi-quantitative drug screening using Enzyme Immunoassay Eia methodology
  • LCMSMS quantitative confirmations on urine & saliva specimens
  • Pharmacogenomics PGx

Menu of Tests


Enzyme-linked Immunoassay (EIA) Screening

  • Amphetamines
  • Barbiturates
  • Benzodiazepines
  • Cannabinoids
  • Cocaine
  • Methadone
  • Methamphetamines
  • Opiates
  • Phencyclidine

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Amphetamines Panel

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Barbiturates Panel

  • Butalbital
  • Pentobarbital
  • Phenobarbital
  • Secobarbital

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Benzodiazepines Panel

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Buprenorphine Panel

  • Buprenorphine
  • Naloxone
  • Norbuprenorphine

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Cocaine Panel

  • Benzoylecgonine
  • Cocaine

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Methadone Panel

  • EDDP
  • Methadone

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Opiates Panel

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Propoxyphene Panel

  • Propoxyphene

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Antidepressants Panel

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Graduated cylinders and beaker filled with chemical compounds

Prescription Medications

  • Amobarbital
  • Aripiprazole
  • Bupropion
  • Buspirone
  • Butabarbital
  • Carisoprodol
  • Chlordiazepoxide
  • Citalopram
  • Codeine
  • Cyclobenzaprine
  • Diphenhydramine
  • Estazolam
  • Fentanyl
  • Flurazepam
  • Gabapentin
  • Lamotrigine
  • Meperidine
  • Meprobamate
  • Methylphenidate
  • Mirtazapine
  • Naltrexone
  • Norfentanyl
  • Paroxetine
  • Pentazocine
  • Phentermine
  • Pregabalin
  • Quetiapine
  • Tapentadol
  • Topiramate
  • Tramadol
  • Trazodone
  • Venlafaxine
  • Zaleplon
  • Zoplicone

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Other Panel & Tests

  • Bath Salts
  • Cathinone (Khat)
  • Cathine (Khat)
  • Cotinine (Naswar)
  • Ethyl Sulfate
  • Dextromethorphan
  • Flunitrazepam (Roofies)
  • K-2 Spice
  • Ketamine
  • Kratom
  • Methaqualone
  • Phencyclidine (PCP)
  • THC Delta 9 (Marijuana)

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Brief Description of Certain Panels & Tests


Amphetamine, commonly prescribed as Adderall is a potent central nervous system (CNS) stimulant, which is used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. It has also been used to treat nasal congestion, depression and obesity, as a cognitive and performance enhancer and illicitly as an aphrodisiac and euphoriant. It leads to fatigue resistance, increased wakefulness and increased muscle strength. At therapeutic doses, amphetamine addiction seldom develops; however recreational doses which are much higher than therapeutic may lead to addiction and very high doses may cause serious side effects such as psychosis. Amphetamine is the parent compound of substituted amphetamines i.e. Methamphetamine, MDMA, MDA and MDEA.


Methamphetamine is widely abused as a recreational drug and is rarely also used to treat ADHD. Its levo form is used in some over-the counter inhalers. The drug is regulated under the Controlled Substances Act and is listed under Schedule II. Recreationally, it is used as a mood enhancer, energy booster and aphrodisiac, allowing some users to engage in continuous sexual activity for several days. Methamphetamine has a high potential for abuse and addiction and long-term use may lead to psychosis. Withdrawal syndrome may last for months beyond the typical withdrawal period.


MDMA commonly known as ‘Ecstasy’ is an amphetamine derivative, banned in most countries, which is associated with dance parties or ‘raves’ and electronic music. It produces a sense of intimacy, diminishing anxiety in interacting with others which can create a sense of euphoria. MDMA is often used along with other recreational drugs including psychedelic drugs such as LSD. Repeated recreational users of MDMA have increased rates of depression and anxiety, even after quitting the drug.


MDA is another banned recreational drug of the Amphetamine class, which has pharmacological mechanism of action and euphoric and empathogenic effects similar to those of MDMA but causes more psychedelic-like effects such as visual hallucinations. Symptoms of acute toxicity may include agitation, sweating, increased blood pressure and heart rate, dramatic increase in body temperature, convulsions and death.


MDEA is a psychedelic drug of the Amphetamine class which has similar mechanism of action as MDMA, however, the euphoric and ‘loved up’ feelings associated with MDMA are not as pronounced in comparison.

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Barbiturates Panel

The Barbiturate panel tests for the presence of butalbital, pentobarbital, phenobarbital and secobarbital. Secobarbital and pentobarbital are short acting barbiturates whereas butalbital is intermediate acting and phenobarbital is long-acting. Butalbital is often combined with other medications and is commonly prescribed for treatment of pain and headache. Both seco and phenobarbital are prescribed for treatment of seizures. All barbiturates have addictive properties.

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Benzodiazepines Panel

Benzodiazepines are a group of psycho-active drugs, which may be short, intermediate or long acting and have sedative, hypnotic, anti-anxiety, anti-convulsant and muscle relaxant properties. They are widely used in the treatment of anxiety, insomnia, agitation, panic, seizures and muscle spasms. Although short term use is usually safe, long term treatment may lead to physical dependence and a withdrawal syndrome on cessation of treatment. Benzodiazepines are considered to be major drugs of abuse, mostly limited to abusers of multiple drugs and are treated as controlled drugs. Benzodiazepines are extensively metabolized and for the most part are detected in urine only as metabolites.

2-Hydroxyethylflurazepam/Desalkyl Flurazepam

2-Hydroxyethylflurazepam/Desalkyl Flurazepam are the metabolites of the long-acting Benzodiazepine, Flurazepam. It has a very long half-life (40-250 hours), and may stay in the blood stream for up to four days. Flurazepam is prescribed for mild to moderate insomnia in the short-term and is given to patients who have difficulty maintain sleep. Prolonged use of Flurazepam is associated with drug tolerance, drug dependence, rebound insomnia and other adverse effects.


Clonazepam is an intermediate acting benzo, which is metabolized to 7-aminoClonazepam. About one third of the patients treated with Clonazepam for more than four weeks develop tolerance, dependence and withdrawal syndrome. It is mainly used for acute management of epilepsies.

Alprazolam/Alpha-Hydroxy Alprazolam

Alprazolam, is a commonly prescribed short-acting Benzodiazepine for the treatment of panic disorder, generalized anxiety (GAD) or social anxiety disorder (SAD) and has a fast onset of action for symptomatic relief. Like other Benzodiazepines, it has the potential for drug dependence and it is in fact, one of the most misused benzodiazepines in the United States. Alpha-Hydroxy Alprazolam is one of the two major metabolites of the drug.


Clordiazepoxide (Librium) was the first Benzodiazepine, discovered by chance. It is a medium to long acting Benzodiazepine but its active metabolite nordiazepam has a very long half-life. It has anxiolytic, hypnotic, muscle relaxant and anti-convulsant properties, the latter being similar to phenobarbital but does not have the same hypnotic effects as the barbiturates and is indicated for short-term (2-4 weeks) treatment of severe and disabling anxiety and for the management acute alcohol withdrawal syndrome. It is metabolized to nordiazepam and oxazepam.

Diazepam (Nordiazepam/Oxazepam/Temazepam)

Diazepam (Valium), the second drug invented after the discovery of the first benzodiazepine Librium is one of the long-acting benzodiazepines and has been one of the most commonly prescribed drug since its discovery in 1963. It is used in the treatment of a number of conditions including anxiety, panic disorder, insomnia, seizures, muscle spasms, restless leg syndrome and alcohol, benzodiazepine and/or opiate withdrawal. Like other benzodiazepines, it has anxiolytic, anti-convulsant, hypnotic, sedative and skeletal muscle relaxant properties and treatment by it carries the risk of tolerance, dependence and benzodiazepine withdrawal syndrome. It is the drug of choice for treating benzodiazepine dependence and for managing acute seizures, anxiety attacks and panic attacks. Diazepam has several active metabolites, the main metabolite being nordiazepam, also a metabolite of Librium. The other metabolites, are oxazepam and temazepam. Very little diazepam is excreted as unmetabolized drug.


Lorazepam (Ativan) is an intermediate-acting benzodiazepine possessing all the common properties of this class of drugs, and is used for the short-term treatment of anxiety, insomnia, acute seizures, sedation of hospitalized patients and sedation of aggressive patients, It carries a higher risk of physical addiction compared to other benzodiazepines and is therefore recommended for short-term (2-4 weeks) use only. Lorazepam is extensively metabolized into pharmacologically inactive metabolites which are excreted as glucuronides.

Midazolam/Alpha-Hydroxy Midazolam

Midazolam is a short-acting benzodiazepine, with an elimination half-life of one to four hours. Its oral form is used in the short-term treatment of severe insomnia unresponsive to other hypnotics, but causes a decline in sleep quality. In combination with an anti-psychotic drug, it is used in the treatment of schizophrenia and is sometimes used in the management of seizures. The IV form of the drug is widely used for procedural sedation needed for example for endoscopies, for pre-operative sedation and for induction of general anesthesia. At last weeks of life, Midazolam at high doses is the preferred mode of palliative deep sedation therapy. Midazolam is metabolized to the pharmacologically inactive alpha hydroxy midazolam.

Alpha-Hydroxy Triazolam

Triazolam (Halcion) has properties similar to other benzodiazepines but is mainly used for short-term treatment of severe insomnia because of its fast onset of action and short half-life. It is used to help with sedation in medical procedures requiring anesthesia, in reducing anxiety during procedures like a MRI scan and as a sleep aid in travelling. Its long-term use is subject to the same concerns of dependency, tolerance, rebound insomnia and CNS related adverse effects as with similar other benzos. Alpha hydroxy triazolam is an inactive metabolite of the drug.


Prazepam is a benzodiazepine indicated for the short –term treatment of anxiety. Its therapeutic effects are due to its active metabolite nordiazepam (also a metabolite of Valium and Librium), which can be considered its pro-drug. Another metabolite 3-hydroxyprazepam is further metabolized to oxazepam


Zolpidem (Ambien) is a non-benzodiazepine hypnotic, short-half life medication for short-term (2-6 weeks) treatment of insomnia and some brain disorders but has not been approved as a muscle relaxant or for seizure prevention. It has not been proven effective in maintaining sleep but aids in sleep initiations. Side effects of sleep walking and even sleep driving have been reported

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Buprenorphine Panel

Buprenorphine (Subutex, Suboxone) is an FDA approved drug for treatment of opioid addiction. Bupenorphine is a partial opioid agonist and a partial antagonist which can negate the effects of a full agonist as morphine and heroin. An opioid agonist produces physiological reactions similar to the substance found in nature whereas an opioid antagonist will combine with and block nerve receptors thwarting the physiological actions of a substance found in nature. By producing enough agonist, individuals taking buprenophine that have become addicted to other opioids are able to discontinue abuse with minimized withdrawl side-effects. Suboxone contains buprenorphine as well as the opioid antagonist naloxone to deter the abuse of tablets by intravenous injection and which can help reverse and even block the effects of a full agonist like heroin. Buprenorphine is metabolized to norbupenorphine which is active and may contribute to the activity of the parent drug. 

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Cocaine Panel

Cocaine, a major drug of abuse is a powerful nervous system stimulant, consumed as fine white powder, inhaled or injected; its effects lasting from fifteen to thirty minutes, to an hour, depending on the amount of intake and route of administration. “Crack” cocaine is a smokeable form of cocaine made into small “rocks” by processing cocaine with sodium bicarbonate (baking soda) and water.
Cocaine enhances feelings of alertness, well-being , euphoria, energy and motor activity, competence and sexuality. Anxiety, paranoia and restlessness can also occur, especially during the comedown. High doses can lead to serious side effects such as tremors, convulsions, severe cardiac adverse events, including sudden cardiac death. Chronic use causes a whole host of adverse medical problems. Regular use of cocaine leads to the psychological dependency of addiction.
Cocaine undergoes extensive metabolism primarily in the liver, with only about 1% excreted unchanged in the urine; with benzoylecgonine being the major metabolite and other significant metabolites in lesser amounts such as ecgonine methyl ester and ecgonine. Benzoylecgonine can be detected in urine within four hours after cocaine intake and remains detectable in concentrations greater than 150 ng/mL typically for up to eight days after cocaine is used.

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Methadone Panel

Methadone is an acyclic analog of morphine or heroin, which is used medically as an analgesic and a maintenance anti-addictive for treatment of patients with opioid dependence and mitigates opioid withdrawal syndrome or makes it more tolerable. At higher doses, methadone can block the euphoric effects of heroin, morphine, and similar drugs. As a result, properly dosed methadone patients can reduce or stop altogether their use of these substances. The duration of methadone maintenance can be for months or even years. As with other opioid medications, tolerance and dependence usually develop with repeated doses.
Methadone and its major metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), are both measurable in urine as part of a drug abuse testing program.

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Opiates Panel

6-Acetyl Morphine (Heroin) 

6- Monoacetyl morphine (6-MAM) is one of the three active metabolites of heroin; morphine is another. Since 6-MAM is a unique metabolite of heroin, its detection in urine confirms the use of heroin unlike the detection of morphine which is a metabolite of a number of opiates both legal and illegal; however 6-MAM has an extremely short half-life and is excreted for only 6-8 hours following heroin intake, so the urine must be collected soon after the last heroin use.


Codeine, an opiate possesses analgesic, antitussive, antidiarrheal, antihypertensive, anxiolytic, antidepressant, sedative and hypnotic properties and has many potential and indicated uses; its most common use being for treatment of mild to moderate pain and to relieve cough. Codeine is currently the most widely used opiate in the world and is one of the most commonly used drugs overall according to numerous reports by various organizations. It can be used as a recreational drug. Codeine is metabolized to morphine. The presence of morphine in urine can indicate exposure to morphine, heroin, or codeine.


Are members of the opiates group which includes morphine and drugs structurally similar to morphine e.g. codeine and oxycodone besides these two, primarily prescribed for pain relief.

Hydrocodone is a semi-synthetic opioid derived from codeine, which is used orally as a narcotic analgesic to treat moderate to severe pain and antitussive (cough medicine), often in combination with paracetamol (acetaminophen) or ibuprofen. Hydrocodone can be habit-forming, causing physical and psychological dependence. Potential for its abuse is similar to that of morphine and less than oxycodone. Severe pain, pins-and-needles sensations throughout the body, sweating, extreme anxiety and restlessness, sneezing, watery eyes, fever, depression, stomach cramps, diarrhea, and extreme drug cravings may accompany withdrawal as is the case with withdrawal symptoms of morphine and other opioids but could be more serious and even lethal unless undertaken under medical supervision. Hydrocodone is metabolized in the liver to hydromorphone, a more potent opioid. Norhydrocodone is a major metabolite.

Hydromorphone, a derivative of morphine and a metabolite of hydrocodone is a very potent opioid, eight times as potent as morphine, and is commonly used in the hospital setting, mostly intravenously (IV) because its bioavailability orally, rectally, and intranasally is very low. Hydromorphone is metabolized to hydromorphone-3-glucoronide which has no analgesic effects. Adverse effects of hydromorphone are similar to those of other potent opioid analgesics, such as morphine and heroin and include dose-related respiratory depression and sometimes circulatory depression. As with other opioids, hydromorphone (particularly during heavy chronic use) often causes temporary hypogonadism or hormone imbalance. Prolonged use may lead to neuroexcitatory symptoms. Like other opiates, hydromorphone can be used recreationally making it susceptible to abuse; however, many patients using it for analgesia are able to use it for extended periods of time without developing drug-seeking behavior. In abusers, there can be a strong psychological dependence, thus creating an addiction with repeated use. Withdrawal is usually short but intense and almost never life-threatening.


Morphine, the gold standard of opioid analgesics, is the main and most abundant psychoactive chemical in opium, and a metabolite of codeine used in clinical medicine to relieve intense pain. It exhibits its analgesic properties by acting directly on the CNS like other opioids, such as oxycodone, hydromorphone, and diacetylmorphine (heroin). Morphine displays a high potential for addiction; heroin and morphine are particularly susceptible to abuse and addiction. Tolerance and psychological dependence develop rapidly, although physiological dependence may take several months to develop. Stopping intake of morphine produces the typical opioid withdrawal syndrome, which, unlike that of barbiturates, benzodiazepines, alcohol, or sedative-hypnotics, is not fatal by itself in neurologically healthy patients without heart or lung problems. In advanced stages of withdrawal, ultrasonographic evidence of pancreatitis has been demonstrated in some patients and is presumably attributed to spasm of the pancreatic sphincter of Oddi. The effects of morphine can be countered with opioid antagonists such as naloxone and naltrexone. Morphine is metabolized primarily in the liver and approximately 87% of a dose of morphine is excreted in the urine within 72 hours of administration. Morphine is metabolized primarily into morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) and into small amounts of normorphine, codeine, and hydromorphone.


Oxycodone, a semi-synthetic opioid is a narcotic analgesic generally indicated for relief of moderate to severe pain, which is one of the most commonly abused prescription medications. It is available both as a single-ingredient medication and in combination products formulated with non-narcotic ingredients such as NSAIDs and paracetamol (acetaminophen). A combination with naloxone is available in managed-release tablets. Like other opioids, oxycodone carries the risk of dependency. Physically dependent and addicted individuals are at high risk of experiencing severe withdrawal symptoms or if the drug is discontinued abruptly. Oxycodone is metabolized to the more potent opioid oxymorphone, which is sold as an analgesic and then to noroxymorphone and noroxycodone.

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Propoxyphene Panel

Dextropropoxyphene, ( Darvon, Darvocet) 

is an opioid analgesic intended to treat mild pain, alone and in combination with acetaminophen or aspirin, which also has antitussive (cough suppressant) and local anaesthetic properties. It was taken off the European and the US markets due to concerns of fatal overdoses and heart arrhythmias, in 2010


is a major metabolite of propoxyphene and is responsible for many of the side effects associated with use of this drug, especially the unusual toxicity seen during propoxyphene overdose It produces prolonged intracardiac conduction time and can lead to heart failure following even relatively minor overdoses. The toxicity of this metabolite makes propoxyphene abuse up to 10 times more likely to cause death following overdose compared to other similar mild opioid analgesics.

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Antidepressants Panel


Amitriptyline (Elavil, Endep, Levate, and many others) is the most widely used tricyclic antidepressant (TCA). It is used to treat a number of mental disorders, including major depressive disorder and anxiety, and less commonly psychosis, attention deficit hyperactivity disorder, and bipolar disorder. Other uses include prevention of migraines and postherpetic neuralgia, and less commonly insomnia.

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Clomipramine (trademarked as Anafranil and Clofranil) is a tricyclic antidepressant (TCA). It was developed in the early 1960s by the Swiss drug manufacturer Geigy (now known as Novartis) and has been in clinical use worldwide ever since. It is the chlorinated derivative of the earlier tricyclic, imipramine. Clomipramine has a number of uses in medicine including in the treatment of Obsessive compulsive disorder (OCD), Major depressive disorder (MDD), Panic disorder with or without agoraphobia, Body Dysmorphic Disorder, Cataplexy associated with narcolepsy, Premature ejaculation, Depersonalization disorder, Chronic pain with or without organic disease, particularly headache of the tension type., Enuresis (involuntary nightly urinating in sleep) in children and adolescents and Trichotillomania. Obsessive compulsive disorder (OCD) is Clomipramine’s only US FDA-labeled indication.

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Desipramine (also known as desmethylimipramine) is a tricyclic antidepressant (TCA). It inhibits the reuptake of norepinephrine and to a minor extent serotonin. It is used to treat depression, but not considered a first line treatment since the introduction of SSRI antidepressants. Desipramine is an active metabolite of imipramine. It is sold under the brand names Norpramin and Pertofrane.
It is primarily used for the treatment of depression. It may also be useful to treat symptoms of attention deficit hyperactivity disorder. Evidence of benefit is only in the short term and with concerns of side effects its overall usefulness is not clear. It has also been tried, albeit with little evidence of efficacy, in the treatment of cocaine dependence. Evidence for usefulness in neuropathic pain is also poor.

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Doxepin is a tricyclic antidepressant marketed worldwide. Brand names of oral formulations include Deptran and Sinequan, and brand names of topical (cream) formulations include Prudoxin. Doxepin is used to treat depression, anxiety disorders, pruritus, insomnia, and as a second-line treatment of chronic idiopathic urticaria (hives). Its oral formulations are FDA-approved for the treatment of depression, anxiety, and insomnia and its topical formulations are FDA-approved for the short-term management (up to 8 days) of atopic dermatitis and lichen simplex chronicus.

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Imipramine, sold as Tofranil and also known as melipramine, is a tricyclic antidepressant (TCA) of the dibenzazepine group. Imipramine is mainly used in the treatment of major depression and enuresis (inability to control urination). It has also been evaluated for use in panic disorder. Imipramine is used in the treatment of depression, such as depression associated with agitation or anxiety and is similar in efficacy to the antidepressant drug moclobemide. It has also been used to treat nocturnal enuresis because of its ability to shorten the time of delta wave stage sleep, where wetting occurs.

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a selective serotonin reuptake inhibitor was approved by the FDA for the treatment of major depressive disorders in December 1987 under the brand name Prozac. With the expiration of the US patent in August 2001, generic formulations became available. It is the third most prescribed antidepressant after sertraline and citalopram. An abrupt stop to treatment by fluoxetine may cause severe withdrawal or discontinuation symptoms; however, the side effects of the fluoxetine discontinuation are milder as compared to those of sertraline and paroxetine. Fluoxetine main metabolite, which is biologically active is norfluoxetine.

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Norclomipramine is a Tricyclic antidepressant. It is an active metabolite of clomipramine that preferentially blocks the norepinephrine transporter.

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Nordoxepin is a Tricyclic antidepressant. It is an active metabolite of doxepin.

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Nortriptyline is a tricyclic antidepressant. It is used to treat symptoms of depression.

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is a SSRI antidepressant which was introduced by Pfizer in 1991 under the name Zoloft, primarily prescribed for major depressive disorder in adult outpatients as well as obsessive–compulsive, panic, and social anxiety disorders in both adults and children. In 2011, it was the second-most prescribed antidepressant in the U.S. It may work better than fluoxetine (Prozac) for some subtypes of depression. Abrupt interruption of sertraline treatment may result in withdrawal or discontinuation syndrome.

Norsertraline is sertraline’s chief active metabolite, which is significantly less active than the parent compound

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Trimipramine (Surmontil, Rhotrimine, Stangyl) is a tricyclic antidepressant (TCA) with antipsychotic and sedative properties. Trimipramine’s primary use in medicine is in the treatment of major depressive disorder, especially where sedation is required due to its prominent sedative effects. Trimipramine also has some weak antipsychotic effects which are less pronounced than with the phenothiazine antipsychotic perazine. Trimipramine is the only effective drug against insomnia known so far that does not alter the normal sleep architecture (there is evidence in medical journals that refute this last statement). In particular, it does not suppress REM sleep, and dreams are said to brighten during treatment.

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Prescription Medications

This section describes testing to determine compliance with prescribed medications, some of which are abused as well. Most of the tests have already been covered under the appropriate panels. Only those not covered are discussed here

Cariprodol (Soma) 

aCarisoprodol, sold by itself or in combination with aspirin, codeine or caffeine is a centrally acting skeletal muscle relaxant. It is a modification of meprobamate and its pro-drug and/or potentiator of hydrocodone, dihydrocodone, dihydrocodeine, codeine and similar drugs and therefore has abuse potential. I has been taken off the market in several countries but is still available in the United States. Carisoprodol, meprobamate, and related drugs such have the potential to produce physical dependence with prolonged use. Withdrawal of the drug after extensive use may require hospitalization in medically compromised patients. Carisprodol is abused for recreational use for its sedating, relaxant and anti-anxiety properties and in conjunction with many opioid drugs. Carisoprodol has a rapid, 30-minute onset of action and is metabolized in the liver mostly to meprobamate, which is a known drug of abuse and dependence.

Cyclobenzaprine (Flexeril)

is a muscle relaxant used to relieve skeletal muscle spasms and associated pain in acute musculoskeletal conditions and has also been used off-label for treatment of fibromyalgia. Flexeril decreases pain in the first two weeks peaking in the first few days, but has no proven benefit after two weeks after which therapy should be discontinued. There is no evidence that discontinuance of treatment by this drug causes intense physical and psychological withdrawal symptoms such as those which occur with benzodiazepine, barbiturate, and carbamate medications. Cyclobenzaprine has major contraindications with monoamine oxidase inhibitors (MAOIs). It is excreted in urine as inactive glucuronide metabolites.


is a powerful, synthetic opioid analgesic, 80-100 times more potent than morphine, with a rapid onset and short duration of action which is used to treat breakthrough pain and is commonly used in pre-procedures as a pain reliever as well as an anesthetic in combination with a benzodiazepine. Fentanyl transdermal patch is used in chronic pain management. The patches work by releasing fentanyl into body fats, which then slowly release the drug into the bloodstream over 48 to 72 hours, allowing for long-lasting pain management. Fentanyl is one of a small number of drugs that may be especially harmful, and in some cases fatal, with just one dose, if used by someone other than the person for whom the drug was prescribed.. Fentanyl and its analogues have been abused for illicit purposes; the biological effects being similar to those of heroin but the potency of the analogues is hundreds of times more than that of heroin making them more dangerous.

Gabapentin (Neurontin)

is an anticonvulsant and analgesic drug which was originally developed to treat epilepsy, and is currently also used to relieve neuropathic pain and as a first line agent for the treatment of neuropathic pain arising from diabetic neuropathy and post-herpetic neuralgia, as well as for many off-label uses, such as treatment of restless leg syndrome, anxiety disorders, insomnia, and bipolar disorder. Pregabalin (Lyrica) is a related drug. In humans, gabapentin doesn’t undergo any biotransformation.

Pregabalin (Lyrica)

As stated above pregabalin, an anticonvulsant, is a related drug to gabapentin and is used for the treatment of neuropathic pain and as an adjunct therapy for partial seizures with or without secondary generalization in adults. It is effective at treating some causes of chronic pain such as fibromyalgia but not others and is not considered to be effective in the treatment of acute pain.It is considered to have a low potential for abuse, and a limited dependence liability if misused, but may cause withdrawal effects after long-term use if discontinued abruptly. Like gabapentin, pregabalin undergoes negligible metabolism in humans and is excreted in the urine as unchanged drug.

Meperidine (Pethidine) (Demerol)

is an older, once popular synthetic opioid analgesic, indicated for the treatment of moderate to severe pain, taken orally or by intramuscular, subcutaneous or intravenous injection. Because of its greater toxicity than other opioids, it is no longer used as an analgesic in labor and delivery but is used preferably for pain control in diverticulitis, because it decreases intestinal intraluminal pressure. Pethidine has serious interactions that can be dangerous with monoamine oxidase inhibitors. Like other opioid drugs, Meperidine has the potential to cause physical dependence or addiction and may be more likely to be abused than other prescription opioids, perhaps because of its rapid onset of action. Pethidine is metabolized primarily to norpethidine which has half the analgesic activity of pethidine but a longer elimination half-life (8–12 hours) accumulating with regular administration, or in renal failure. Norpethidine is toxic and has convulsant and hallucinogenic effects as well as serotonergic effects which means that unlike most opioids, it could contribute to serotonin syndrome. Pethidine’s metabolites are further conjugated with glucuronic acid and excreted into the urine.

Quetiapine (Seroquel)

is a short-acting atypical antipsychotic used for the treatment of schizophrenia, bipolar disorder, and along with an antidepressant to treat major depressive disorder; but has a host of side-effects. It should be discontinued gradually to avoid withdrawal symptoms or relapse. Most instances of acute overdosage result only in sedation, hypotension and tachycardia, but cardiac arrythmia, coma and death have occurred in adults. Abuse of the drug, by oral intake, snorting pulverized tablets or intravenous administration for recreational use is driven by its sedative and anxiolytic effects rather than by its antipsychotic properties. Quetiapine is extensively metabolized in the liver through sulfoxidation, N- and O- dealkylation and to a lesser degree through 7-hydoxylation. The most important active metabolite of quetiapine appears to be n-desalkylquetiapine. Less than 1% of the drug is excreted in the unmetabolized form.

Tapentadol (Nucynta)

is a centrally fast acting analgesic, approved in 2011, with a dual mode of action, like that of tramadol, as an agonist of the μ-opioid receptor and as a norepinephrine reuptake inhibitor but has only weak effects on the reuptake of serotonin. It is a significantly more potent opioid and has no known active metabolites. Tapentadol is indicated for the treatment of moderate to severe pain for both acute and chronic musculoskeletal pain. It is also specifically indicated for controlling the pain of diabetic neuropathy when around-the-clock opioid medication is required and is often used off-label for treatment of non-diabetic neuropathic pain. Dependence which can lead to addiction generally follows regular use of Nucynta producing unpleasant withdrawal symptoms when the dependent person attempts to abruptly discontinue use of the drug. Combination with SSRIs/SNRIs, SRAs, serotonin receptor agonists and/or MAOIs may lead to potentially lethal serotonin syndrome. Concurrent use with MAOIs may also result in an adrenergic storm. Combination with alcohol, and/or other sedatives increases the risk for many of tapentadol’s side effects. Due to its actions on norepinephrine, and to a lesser extent serotonin, a tapentadol overdose may produce symptoms which are not typically present in opioid overdoses (symptoms of serotonin syndrome and adrenergic syndrome). This risk is greater if tapentadol has been taken with other drugs of similar mechanisms.


Taramadol, a centrally acting analgesic opioid is used to treat moderate to severe pain, both acute and chronic, often combined with paracetamol, and has a mechanism of action similar to that of tapentadol, with additional serotonin-norepinephrine reuptake-inhibiting effects. Tramadol is primarily metabolised to O-desmethyltramadol, which is a significantly more potent opioid with additional norepinephrine reuptake-inhibiting properties, making it analogous to tapentadol. When taken as an immediate-release oral formulation, the onset of pain relief usually occurs within about an hour.. Tramadol has about one-tenth the potency of morphine and is approximately equally potent when compared to pethidine and codeine. It interacts, potentially fatally, with such toxicity to epinephrine/norepinephrine receptors. Long-term use of high doses of tramadol may be associated with physical dependence and a withdrawal syndrome, with symptoms typical of both opiate withdrawal and those associated with SSRI withdrawal. Because of the possibility of convulsions at high doses for some users, recreational use can be very dangerous. Tramadol can cause a higher incidence of nausea, dizziness, loss of appetite compared with opiates, which could deter abuse. Compared to hydrocodone, fewer persons choose to abuse tramadol.

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Individual Tests

Bath salts 

The name Bath Salts covers a number of recreational designer drugs, which pharmacologically usually contain a cathinone, typically methylenedioxypyrovalerone (MDPV), methylone or mephedrone; however, the chemical composition varies widely and products labeled with the same name may also contain derivatives of pyrovalerone or pipradrol. Not much information is available on how bath salts interact with the brain and how they are metabolized by the body. They seem to have a powerful addictive potential and can increase users’ tolerance. Like amphetamines, they cause stimulant effects by increasing the concentration of monoamines such as dopamine, serotonin, and norepinephrine in synapses. Bath salts are can be swallowed, snorted, smoked, or injected. They are illegal in most states.


Diphenylhydramine (Benadryl)

is a commonly used, over the counter, first-generation antihistamine and sleep-aid possessing anticholinergic, antitussive, antiemetic, and sedative properties that is mainly used to treat allergies. A prescription-only injectable diphenhydramine can be used for life-threatening reactions (anaphylaxis) to allergens such as bee stings, peanuts, or latex, as an adjunct to epinephrine. As a potent antagonist to acetylcholine in muscarinic receptors, diphenhydramine is used to treat Parkinson’s disease-like extrapyramidal symptoms caused by antipsychotics.

Because of its strong sedative properties, diphenhydramine is widely used in nonprescription sleep aids for insomnia and is an ingredient in several products sold as sleep aids, either alone or in combination with other ingredients such as acetaminophen (paracetamol). Tolerance against the sedating effect of diphenhydramine builds very quickly within 2-3 days.

The primary route of metabolism is two successive demethylations of the tertiary amine. The resulting primary amine is further oxidized to the carboxylic acid.

Diphenhydramine is sometimes used recreationally as a potentiator of alcohol, opiates, DXM and other depressants but has a limited abuse potential in the United States due to its potentially serious side-effect profile and limited euphoric effects. It is sometimes used as a recreational drug, often by those without access to illegal drugs for its sedative properties and (at higher doses) and to intensify the effects of opioids. Recreational use of diphenhydramine may cause a number of ill-effects including death.

K-2 Spice

K2 and Spice are genericized trademarks used for any synthetic cannabis products. A large and complex variety of synthetic cannabinoids, most often cannabicyclohexanol, JWH-018, JWH-073, or HU-210, are used in an attempt to avoid the laws that make cannabis illegal, making synthetic cannabis a designer drug. Synthetic cannabis does not produce positive results in urine drug screening tests for cannabis but it is possible to detect its metabolites in human urine. Synthetic cannabis may precipitate psychosis, which may be prolonged in some cases, may cause worsening of previously stable psychotic disorders, and it may trigger a chronic (long-term) psychotic disorder among vulnerable individuals such as those with a family history of mental illness. The adverse effects of synthetic cannabinoids are often much more severe than those due to cannabis and THC.

Pencyclidine (PCP)

PCP was introduced in the 1950s as an anesthetic but because of its long half-life and adverse side effects it was removed from the market in 1965 and limited to veterinary use. It is a recreational dissociative drug of abuse, but its use has been steadily declining. More than 30 different analogues of PCP were reported as being used on the street during the 1970s and 1980s, mainly in the USA. As a recreational drug, PCP may be ingested, smoked, inhaled or injected. Recreational doses of the drug occasionally appear to induce a psychotic state that resembles a schizophrenic episode, sometimes lasting for months at a time. Users generally report feeling detached from reality. PCP is metabolized into PCHP, PPC and PCAA. When smoked, some of it is broken down by heat into 1-phenyl-1-cyclohexene (PC) and piperidine.

THC Delta 9

is the principal psychoactive constituent (or cannabinoid) of the cannabis plant. A pharmaceutical formulation of (−)-trans-Δ9-tetrahydrocannabinol,is available by prescription in the U.S. and Canada under the brand name Marinol. THC has mild to moderate analgesic effects causes relaxation, alteration of visual, auditory, and olfactory senses, stimulates appetite and has marked antiemetic properties. It may acutely reduce aggression and increase aggression during withdrawal. There is evidence supporting the efficacy of cannabis extracts and THC in treating certain symptoms of multiple sclerosis, alleviating symptoms suffered both by AIDS patients and by cancer patients undergoing chemotherapy by increasing appetite and decreasing nausea. THC intoxication is well established to impair cognitive functioning on an acute basis, including effects on the ability to plan, organize, solve problems, make decisions, and control impulses. THC is metabolized mainly to 11-OH-THC by the body. This metabolite is still psychoactive and is further oxidized to 11-nor-9-carboxy-THC (THC-COOH). In humans there are more than 100 identifiable metabolites, but 11-OH-THC and THC-COOH are the dominating metabolites. More than 55% of THC is excreted in the feces and ~20% in the urine. The main metabolite in urine is the ester of glucuronic acid and THC-COOH and free THC-COOH.

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