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Drug Detection Times in Urine

Drug/IdentifierMinimumMaximumCut-Off Level
Marijuana (THC)†2 hoursUp to 40+ days50 ng/ml
Cocaine (COC) †1-4 hours2-4 days300 ng/ml
Methamphetamine (METH) †2-7 hours2-4 days1000 ng/ml
Amphetamines (AMP) †2-7 hours2-4 days1000 ng/ml
Ecstasy (MDMA) †2-7 hours2-4 days500 ng/ml
Opiates (OPI) †2 hours2-3 days2000 ng/ml
Phencyclidine (PCP) †4-6 hours7-14 days25 ng/ml
Benzodiazepines (BZO)2-7 hours1-4 days300 ng/ml
Methadone (MTD)3-8 hours1-3 days300 ng/ml
Barbiturates (BAR)2-4 hours1-3 weeks300 ng/ml
Tricyclic Antidepressants (TCA)8-12 hours2-7 days1000 ng/ml
Oxycodone (OXY)1-3 hours1-2 days100 ng/ml

† The Substance Abuse and Mental Health Services Agency (SAMHSA), has set "cut-off" levels when testing for marijuana, cocaine, methamphetamine, amphetamines, ecstasy, opiates, and PCP. First Check is manufactured to conform to those standards. Screening tests may not detect amounts of drugs in a urine sample that are below the cut-off level. Even though some level of drug may be present in a urine sample, the sample would still be considered Negative Result if the drug level is below the cut-off level.


What is it?

This family of depressants affects the central nervous system and is widely prescribed for the treatment of insomnia, anxiety, and prevention of seizures and muscle spasms. Most patients use it as prescribed, but adolescents and young people who abuse these drugs are seeking a “high.” Physical dependence can be caused by high dose or long-term use. The drug is also doctor-shopped by adult users. Drug abusers often use benzodiazepines to “come down,” or ease withdrawal from a stimulant drug, such as methamphetamine. High doses of these drugs, with alcohol alone or other depressants, can cause death. A benzodiazepine that is illegally marketed in the U.S., flunitrazepam (rohypnol) is a dangerous, long acting “club drug,” that can be mixed in a victim’s drink. This has notoriously resulted in sexual assault. Common prescription benzodiazepines include the trade names Valium, Xanax, Librium, and Ativan.

Slang Terms:

Rohypnol may be called rophies, roofies, and roach. Others slang terms include benzos, downers, tranks.

How is it used?

These drugs are most commonly taken in pill form, but can be used in powder form and mixed in water or drinks. They are sometimes taken in combination with other drugs or alcohol. They are also used by abusers with GHB (gamma hydroxybutyrate) and similar drugs that are marketed as nutritional supplements.

Signs of usage:

Those who take rohypnol are in a near trance-like state or appear drunk, even with hangover like effects in withdrawal. Those who take high doses of other benzodiazepines may appear drunk or uninhibited.

Effects of usage:

In prescription form, benzodiazepines are therapeutic, but long-term use can cause addiction. Used to get a high or induce a drunken-like state, the drugs lessen inhibitions and impair judgment. Rohypnol causes a stupor-like state.

How long do the effects last?

The effects of rohypnol are fast-acting and can last 4 to 8 hours. Short-acting benzodiazepines have a half-life of less than 12 hours. Intermediate-acting compounds have a half-life of 12-24 hours, and may cause inattention or sluggishness the morning after taking.

Effects of withdrawal:

Withdrawal symptoms are mainly anxiety-related. These effects occasionally go on for months, and may include insomnia and gastrointestinal problems, even when use is gradually reduced. Abrupt discontinuation of prescription benzodiazepines can cause these symptoms as well as seizures and hyperactivity.

Adverse reactions:

Rohypnol causes sedation and sluggishness and can also cause amnesia, resulting in a person not remembering what happens during the drug-induced stupor. Users are at a high risk for sexual assault. The effects of benzodiazapine may linger for hours, causing inattention to tasks, such as driving. For some users, the use of benzodiazepines can cause high anxiety and irritability instead of the intended sedation. At high doses, and/or with other drugs, benzodiazepines can be deadly.

Effects of prolonged usage:

Even when used therapeutically, benzodiazepines can cause decreased attention span when used for more than a year. Physical addiction can occur with abuse or even prolonged therapeutic use.

Usage by youth:

Rohypnol is characteristically a “club” drug taken by young people. It is hard to determine the use of this drug as a date rape or club-rape drug because often the victim has no memory of the assault. When adolescents abuse prescription benzodiazepines, they take higher doses for a kind of drunken high.

Recent Developments:

The use of rohypnol as a “club” drug is so dangerous that the manufacturer and U.S. agencies have been working to reduce its availability in this country. However, rohypnol and other socalled “club” drugs are currently available on the Internet. Young people are also taking the drug in combination with growth hormones and GHB in cleaning solvents.
*Information provided by Dr. Barbara A. Krantz, Chief Medical Officer at the Hanley Center
*First Check Diagnostics Corp. is offering these resources for informational purposes only, and the Hanley Center is no way affiliated with any of the entities that provide the resources.