Drug panel codes, testing methods, detection windows, and your rights.
URINE DRUG TESTING
REFERENCE GUIDE
For Federal Halfway Houses, RRCs, and Supervised Release
A DrPrison.org Reference Guide
Plain-Language. Field-by-Field. Honest.
DISCLAIMER This guide is for educational and informational purposes only. It is not legal advice, medical advice, or a recommendation to consume any substance. DrPrison.org provides reference materials to help individuals understand the processes and systems they encounter during federal reentry. Always consult with your attorney, supervising officer, or medical provider for guidance specific to your situation. |
1. Understanding Urine Drug Testing in Federal Supervision
If you are in a federal Residential Reentry Center (RRC, also known as a halfway house), on supervised release, or on federal probation, urine drug testing (urinalysis or UA) is a standard part of your supervision. This guide explains what is being tested, how to read the codes on your test results, how the science actually works, and what your rights are.
Federal halfway houses and probation offices primarily use two methods of urine testing:
Immunoassay (rapid screening): A quick, on-site test using dip cards, cups, or cassettes (commonly Alere/Abbott brand products like the iScreen or iCup). Results in minutes. This is the first-level screening.
GC/MS or LC/MS/MS (confirmation testing): If a rapid screen comes back positive, the specimen should be sent to an HHS-certified laboratory for confirmation using gas chromatography/mass spectrometry. Federal law requires this confirmation step before any sanction.
KEY POINT: SCREENING vs. CONFIRMATION A positive rapid screen is NOT a confirmed positive. Under 18 U.S.C. § 3563(e) and § 3583(d), a drug test confirmation for an initial positive result must be confirmed using GC/MS, LC/MS/MS, or an equivalent method approved by the Director of the Administrative Office of the Courts. You have the right to request confirmation testing. |
2. Drug Panel Codes: What the Letters on Your Test Mean
The abbreviations printed on rapid test devices (Alere iCup, iScreen, Drug Confirm, etc.) correspond to specific drug classes. Below is a complete reference for every code you may encounter on a standard 5-panel through 16-panel urine test, along with the typical cutoff level and approximate detection window.
| Code | Substance | Cutoff | Common Names / Prescriptions | Detection |
| AMP | Amphetamines | 1000 ng/mL | Adderall, Dexedrine, Vyvanse | 1-4 days |
| mAMP / MET | Methamphetamine | 1000 ng/mL | Crystal meth, Desoxyn | 2-5 days |
| BAR | Barbiturates | 300 ng/mL | Phenobarbital, Seconal | 1-7 days |
| BZO | Benzodiazepines | 300 ng/mL | Xanax, Valium, Klonopin, Ativan | 1-7 days |
| BUP | Buprenorphine | 10 ng/mL | Suboxone, Subutex | 1-3 days |
| COC | Cocaine | 300 ng/mL | Crack, cocaine hydrochloride | 2-4 days |
| ETG | Ethyl Glucuronide (Alcohol) | 500 ng/mL | Beer, wine, liquor | 24-80 hours |
| FEN | Fentanyl | Varies | Fentanyl patches, illicit fentanyl | 1-3 days |
| K2 | Synthetic Cannabinoids | 25 ng/mL | Spice, K2 | 2-3 days |
| MDMA | Ecstasy / Molly | 500 ng/mL | MDMA, MDA | 2-4 days |
| MTD | Methadone | 300 ng/mL | Dolophine, Methadose | 1-5 days |
| OPI | Opiates | 2000 ng/mL | Morphine, codeine, heroin | 2-4 days |
| OXY | Oxycodone | 100 ng/mL | OxyContin, Percocet | 1-4 days |
| PCP | Phencyclidine | 25 ng/mL | Angel dust, PCP | 7-14 days |
| PPX | Propoxyphene | 300 ng/mL | Darvon, Darvocet | 1-2 days |
| TCA | Tricyclic Antidepressants | 1000 ng/mL | Amitriptyline, Nortriptyline | 2-7 days |
| THC | Marijuana / THC | 50 ng/mL | Cannabis, edibles, concentrates | 3-30+ days |
| TRA | Tramadol | 100 ng/mL | Ultram, ConZip | 1-3 days |
Note: Detection windows are approximate and vary significantly based on body weight, metabolism, hydration, frequency of use, and individual physiology. Chronic marijuana users, for example, may test positive for THC for 30 days or longer after last use.
Common Panel Configurations
5-Panel (Standard Federal Workplace): AMP, COC, OPI, PCP, THC. This is the baseline required by federal mandatory guidelines.
10-Panel (Common for RRCs): Adds BAR, BZO, MTD, MAMP, and either OXY or PPX to the 5-panel.
12-Panel (Extended): Typically adds BUP, ETG, and/or TRA to the 10-panel.
As of 2025, HHS has been working to add fentanyl (FEN) to the mandatory federal testing panels due to the role of illicit fentanyl in overdose deaths. Expect FEN to appear on more test panels going forward.
3. Specimen Validity Codes (Adulteration Detection)
In addition to drug panels, most rapid test cups include an adulteration detection (AD) strip. These are the codes printed on Alere/Abbott test cups, typically shown as CR-GL-NI-OX-PH-SG. They check whether the specimen has been tampered with.
| Code | What It Tests | What It Means |
| CR | Creatinine | Checks for dilution. Normal: 20-300 mg/dL. Below 20 mg/dL = dilute specimen. |
| SG | Specific Gravity | Checks for dilution. Normal: 1.003-1.030. Below 1.0030 = dilute specimen. |
| PH | pH Level | Detects acids or bases added to urine. Normal: 5.0-8.0. |
| NI | Nitrites | Detects chemical adulterants sometimes used to defeat testing. |
| GL | Glutaraldehyde | Detects another common commercial adulterant product. |
| OX | Oxidants | Detects bleach, pyridinium chlorochromate (PCC), and similar oxidizing agents. |
Specimen Result Categories
Negative: No drugs detected above the cutoff level.
Positive: One or more substances detected above the cutoff level. Must be confirmed by GC/MS.
Dilute: Creatinine between 2-20 mg/dL with specific gravity between 1.0010-1.0030. You will typically be required to retest. Repeated dilute specimens may be treated as a violation.
Substituted: Creatinine and specific gravity values are so far outside normal range that the specimen is not consistent with human urine. Treated as a refusal to test.
Adulterated: A foreign substance was detected, or an endogenous substance is at an abnormal concentration. Treated as a refusal to test.
Invalid: Results could not be determined. You will be required to retest, often under direct observation.
4. ETG Alcohol Testing: What the Science Actually Shows
Ethyl Glucuronide (ETG) is a metabolite your body produces when it processes alcohol. Unlike standard ethanol tests (which only detect alcohol for a few hours), ETG testing can detect that alcohol was consumed days earlier. This makes it the preferred test for abstinence monitoring in federal supervision.
How ETG Works
When you drink any alcohol, your liver metabolizes the ethanol. A small portion (less than 0.1%) is converted into ETG, which is then excreted through your kidneys into your urine. ETG does not measure impairment or intoxication. It only confirms that ethanol entered your body at some point within the detection window.
Cutoff Levels and What They Mean
100 ng/mL: Very sensitive. Detects any alcohol exposure, including incidental contact with alcohol-containing products. Rarely used in federal supervision because of high false positive risk.
250 ng/mL: Moderate sensitivity. Some labs and programs use this as a middle ground.
500 ng/mL: Standard cutoff for most federal supervision programs, recommended by SAMHSA. Designed to minimize false positives from incidental exposure while still detecting intentional drinking.
Realistic Detection Windows by Consumption Level
The following table is based on peer-reviewed clinical studies. These are estimates, not guarantees. Individual results vary based on metabolism, body size, hydration, and liver function.
| Amount Consumed | Cutoff | Peak Detection Risk | Likely Clear By |
| 1 standard drink | 100 ng/mL | Likely positive up to 24 hours | Likely positive up to 12-18 hours |
| 1 standard drink | 500 ng/mL | Likely positive up to 12 hours | Most likely negative by 18 hours |
| 2-3 standard drinks | 100 ng/mL | Likely positive up to 48 hours | Likely positive up to 36 hours |
| 2-3 standard drinks | 500 ng/mL | Likely positive up to 24 hours | Likely positive up to 20 hours |
| 4-6 standard drinks | 100 ng/mL | Likely positive up to 72 hours | Likely positive up to 48 hours |
| 4-6 standard drinks | 500 ng/mL | Likely positive up to 48 hours | Likely positive up to 36 hours |
| Heavy drinking (6+) | 500 ng/mL | Likely positive up to 72-80 hours | Likely positive up to 48-60 hours |
CRITICAL: DEHYDRATION CONCENTRATES YOUR URINE If you are dehydrated when you provide a specimen, the concentration of ETG in your urine will be higher than expected for the amount of alcohol consumed. Conversely, overhydration may dilute your specimen below the detection threshold but could also produce a dilute result, which brings its own problems. Normal hydration is always the safest approach. |
What Does NOT Trigger a Positive at 500 ng/mL
Controlled studies have established that the following do not produce ETG levels above 500 ng/mL, even with repeated or heavy use:
Hand sanitizer: Subjects who used hand sanitizer every 15 minutes for 8 hours never exceeded 62 ng/mL.
Mouthwash: 55 subjects used mouthwash 3 times daily for 5 straight days, holding it for 30 seconds each time. The highest ETG concentration was 120 ng/mL.
NyQuil: Three daily doses of 1 oz. of NyQuil (25% alcohol, well above recommended dosage) produced a maximum of only 246 ng/mL.
However, at the more sensitive 100 ng/mL cutoff, these products CAN produce positive results. If your program uses a 100 ng/mL cutoff, you need to be especially careful about alcohol-containing products.
ETG Result Interpretation
Below 100 ng/mL: Negative. No evidence of alcohol exposure.
100-500 ng/mL (Very Low Positive): May indicate incidental exposure to alcohol-containing products, light drinking 1-2 days ago, or heavy drinking 3+ days ago. At a 500 ng/mL cutoff, this would be reported as NEGATIVE.
500-1,000 ng/mL (Low Positive): Consistent with light-to-moderate drinking within the past 1-2 days, or heavy drinking 2-3 days ago.
Above 1,000 ng/mL (High Positive): Strongly indicates intentional alcohol consumption, likely heavy drinking within the past 1-2 days.
5. Your Rights: Disputing a Positive Test Result
A positive urine drug test in the federal system can result in sanctions ranging from increased testing frequency to revocation of supervised release and return to custody. Understanding your rights is critical.
Right to Confirmation Testing
This is your most important right. Under federal law (18 U.S.C. § 3563(e) and § 3583(d)), an initial positive result from a rapid immunoassay screening must be confirmed by GC/MS, LC/MS/MS, or an equivalent approved method before it can be used as the basis for any sanction. A rapid screening alone is not sufficient.
WHAT TO DO IF YOU TEST POSITIVE AND BELIEVE IT IS WRONG 1. Remain calm. Do not argue at the collection site. 2. Immediately request in writing that the specimen be sent to an HHS-certified laboratory for GC/MS confirmation. 3. Document the date, time, the collector, and any substances (prescription medications, supplements, food) you have used in the past 7 days. 4. Contact your attorney. If you do not have one, contact the Federal Defender in your district. 5. If you are on prescribed medication that may cause a positive result, have your prescribing doctor provide documentation. |
Common Causes of False Positives
Immunoassay screening tests use antibodies that react to drug metabolites. But these antibodies can also react to chemically similar substances, producing false positives. The following are well-documented causes:
| Test Panel | Known False Positive Triggers |
| AMP (Amphetamines) | Pseudoephedrine (Sudafed), phenylephrine, Wellbutrin (bupropion), Adderall (if prescribed, provide documentation), selegiline, labetalol |
| BZO (Benzodiazepines) | Sertraline (Zoloft), efavirenz, oxaprozin (Daypro) |
| OPI (Opiates) | Poppy seeds (confirmed in multiple studies), dextromethorphan (cough syrup), rifampin, quinolone antibiotics |
| THC (Marijuana) | Dronabinol (Marinol, if prescribed), hemp-derived CBD products (may contain trace THC), ibuprofen (rare, older assays), pantoprazole (Protonix) |
| PCP (Phencyclidine) | Dextromethorphan (cough syrup), diphenhydramine (Benadryl), tramadol, venlafaxine (Effexor) |
| ETG (Alcohol) | At 100 ng/mL cutoff: hand sanitizer, mouthwash, cooking extracts, certain medications. At 500 ng/mL cutoff: incidental exposure is extremely unlikely to trigger a positive. |
The Medical Review Officer (MRO) Process
In federal workplace testing, an MRO reviews all positive results before they are reported. The MRO contacts you to discuss possible legitimate medical explanations (prescriptions, medical conditions). In the criminal justice system, this MRO step does not always occur automatically. If you are on a prescribed medication that caused a positive result, proactively provide documentation to your supervising officer and request that the result be reviewed by a qualified professional.
Filing a Dispute or Grievance
If you are in an RRC (halfway house) and believe a test result is incorrect:
Request GC/MS confirmation in writing immediately.
File an Administrative Remedy (BP-9) if you are still under BOP jurisdiction. Follow the Administrative Remedy Program process: BP-9 (institution level) within 20 days, BP-10 (Regional Director) within 20 days of response, BP-11 (General Counsel) within 30 days.
If you are on supervised release, notify your attorney and your U.S. Probation Officer in writing. Document everything.
Preserve any evidence: prescription bottles, pharmacy records, food packaging, product labels for anything that may have caused a false positive.
6. Practical Tips for People on Federal Supervision
Before Every Test
Stay normally hydrated. Do not overhydrate (dilute result) or underhydrate (concentrated specimen reads higher).
Keep a personal log of all medications, supplements, and foods you consume. This protects you if a dispute arises.
Carry copies of all prescriptions. If you are on Suboxone, methadone, or any controlled substance, have your prescribing provider on record with your supervising officer.
Know what panel your facility uses (5-panel, 10-panel, etc.) and what cutoff levels apply. You are entitled to ask.
Products to Avoid
Mouthwash containing alcohol (Listerine, etc.) — switch to alcohol-free versions like Crest Pro-Health.
Cooking extracts (vanilla, almond, lemon) — these contain significant alcohol content.
Hemp-derived CBD products — these may contain trace amounts of THC and can trigger a positive on sensitive panels.
Poppy seed bagels, muffins, and pastries — documented to cause opiate positives.
Kombucha and other fermented beverages — these contain trace alcohol.
Some cold medications containing pseudoephedrine or dextromethorphan.
If You Are Prescribed Medication That May Trigger a Positive
You are not required to stop taking prescribed medication because of drug testing. However, you should:
Inform your supervising officer before your first test that you are on prescribed medication.
Provide a copy of your prescription and a letter from your prescribing provider to your supervising officer.
Keep this documentation current. If your prescription changes, update your records.
If a positive result occurs due to prescribed medication, the confirmation test (GC/MS) can distinguish between different substances within the same drug class.
Know the Difference Between a Violation and a Sanction
A single positive drug test does not automatically mean revocation of supervised release or return to custody. Under the federal graduated sanctions framework, responses to violations may include increased testing frequency, increased reporting requirements, community service, substance abuse treatment, or modification of conditions. Revocation typically follows a pattern of repeated violations or failure to comply with treatment. Understanding this framework helps you advocate for yourself.
7. Resources
DrPrison.org — Additional federal reentry reference guides, including the Administrative Remedy Program, BOP Form BP-A0291, and executive clemency.
SAMHSA — Substance Abuse and Mental Health Services Administration. Mandatory Guidelines for Federal Workplace Drug Testing Programs.
Federal Defender Services — Free legal representation for federal defendants. Contact the Federal Public Defender in your district.
Administrative Office of the U.S. Courts — Substance Use Testing & Treatment Reference Guide (March 2020). Available at uscourts.gov.
HHS-Certified Laboratories — A current list is published monthly in the Federal Register. These are the only labs authorized to perform federal workplace confirmation testing.
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