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Blood Test Tracker

Urine Amphetamines Screen

A urine screen for amphetamine-type stimulants, including some prescription medicines. A first positive is presumptive until a second test confirms it.

AI-verified against cited sources. Awaiting expert reviewAlso called AMPLOINC 19261-7

What it is

Amphetamines are stimulant drugs. Some are prescription medicines, such as those used for ADHD, and some are illegal. The urine screen uses a quick test, called an immunoassay, that reacts to amphetamine-like molecules. It reports only positive or negative against a set cutoff, often 500 ng/mL, and it can't tell how much was taken or exactly when. Methamphetamine is usually picked up by the same screen.

Why it matters

Clinicians order this screen to check on prescribed stimulants, to look for causes of symptoms in an emergency, or because a job or program requires it. A screen is not proof of use. A prescribed medicine will test positive on purpose, and some common medicines can cause a false positive. A second test, usually mass spectrometry, shows which substance is really present.

If it’s high

A positive screen means the test reacted at or above the lab's cutoff. That is expected if you take a prescribed amphetamine medicine. Other medicines can also cause a positive reading. A confirmation test on the same sample can tell which substance is present, so an unexpected positive deserves a conversation before conclusions are drawn.

Common causes

  • A prescribed amphetamine-type medicine taken as directed
  • Medicines that cross-react with the test, such as bupropion, trazodone, quetiapine, tricyclic antidepressants and pseudoephedrine
  • Some nonprescription nasal inhalers
  • Methamphetamine or other stimulants that were not prescribed

What can help

  • Tell the clinician and the lab about every prescription, over-the-counter medicine and supplement you take
  • Ask whether the result was confirmed with a second test, and what cutoff the lab used
  • If you take a prescribed stimulant, ask that it be noted next to the result

What can affect your result

  • The cutoff the lab uses (500 ng/mL is common, and some labs use 1,000 or lower levels)
  • The test type: immunoassay screens cross-react with some medicines, while mass-spectrometry screens are more specific
  • How long ago the drug was taken (for most drugs, roughly 1 to 4 days)
  • How dilute the urine is
  • Prescription and over-the-counter medicines
  • Prescribed amphetamine medicines are expected to give a positive screen.
  • Some other medicines can cause a false positive, including bupropion, trazodone, quetiapine, tricyclic antidepressants and pseudoephedrine, and some nonprescription nasal inhalers.
  • Very dilute urine can push a low level under the cutoff and give a negative result.
  • Each lab sets its own cutoff, and kits differ in which related drugs they react to.

Any time. A random urine sample is typical. When results will be used for work or legal reasons, the collection may be observed and the sample temperature checked. Shows recent use only. For most drugs, urine tests can detect use from roughly 1 to 4 days earlier, depending on the dose and how often it was used.

When to talk to a clinician

A positive screen alone is not an emergency. Call 911 or your local emergency number for chest pain, trouble breathing, a seizure, severe confusion or agitation, or a very high fever after stimulant use. In the US, Poison Control is 1-800-222-1222, and the SAMHSA National Helpline (1-800-662-4357) offers free, confidential support for anyone worried about substance use.

Questions you could ask

  • Who will see this result, and how will it be used?
  • Could one of my medicines or supplements explain this result?
  • Was this result confirmed with a second, more specific test?
  • What cutoff did this lab use?

Questions people ask

Will my prescribed ADHD medicine show up?

Yes. Prescribed amphetamine medicines are expected to read positive on this screen. Tell the clinician and the lab you take one, so the result can be read in that light.

Can other medicines cause a false positive?

Yes. Examples reported include bupropion, trazodone, quetiapine, tricyclic antidepressants and pseudoephedrine. A confirmation test on the same sample can tell a false positive from a true one.

How long can a urine test pick up amphetamines?

It depends on the dose, how often it was used and how your body handles it. For most drugs, urine tests can detect use from roughly 1 to 4 days earlier.

Show the science and sources

For clinicians and researchers

Urine amphetamine screens are immunoassays (for example the homogeneous Syva EMIT II, or lateral-flow devices) that are calibrated with a target analyte, react to related drugs to varying degrees, and are reported as presumptive positive or negative against a cutoff. The federal workplace panel uses an initial test cutoff of 500 ng/mL for amphetamine and methamphetamine, with confirmation at 250 ng/mL (49 CFR 40.85). Clinical labs commonly use 500 ng/mL, and LOINC has screen codes for both 500 and 1,000 ng/mL. A hospital lateral-flow screening device described in 2025 used 500 ng/mL for amphetamines. Mayo Clinic Laboratories uses an LC-MS/MS stimulant screen with a 100 ng/mL cutoff and reports not detected or present, while Labcorp screens by immunoassay and confirms positives by mass spectrometry. Cross-reactivity is the main limit. Merck Manual lists pseudoephedrine, tricyclic antidepressants and quetiapine. A 2024 study found that m-chlorophenylpiperazine, the main metabolite of trazodone, triggers one amphetamine immunoassay (Thermo DRI). A pharmacy review (Brahm 2010) found amphetamine and methamphetamine to be the most commonly reported false-positive drug screens, with reports across antihistamines, antidepressants, antibiotics, analgesics, antipsychotics and a nonprescription nasal inhaler. In an emergency department series of 10,011 screens (Syva EMIT II), 362 (3.6%) were amphetamine-positive, 35% of those failed to confirm by gas chromatography, and bupropion use was recorded in 41% of the unconfirmed ones. Immunoassay positives are presumptive until confirmed by a second independent method (Saitman 2014). Urine drug testing cannot determine how much was taken or how often (Merck Manual).

LOINC 19261-7 (primary), 43983-6, 14308-1, 113958-3, 3349-8. Specimen: urine.

Sources

  1. Drug Testing, Merck Manual Professional Version (2026)
  2. Drug Testing, MedlinePlus (National Library of Medicine)
  3. Commonly prescribed medications and potential false-positive urine drug screens, American Journal of Health-System Pharmacy (2010)
  4. False-positive interferences of common urine drug screen immunoassays: a review, Journal of Analytical Toxicology (2014)
  5. Abnormal Urine Drug Screens in Pregnancy: Opportunity for Laboratory Stewardship, EJIFCC (IFCC) (2025)
  6. 49 CFR 40.85: What are the cutoff concentrations for urine drug tests?, Electronic Code of Federal Regulations (US Department of Transportation)
  7. Amphetamines, Screen and Confirmation, Urine (test 074401), Labcorp
  8. TSPU: Targeted Stimulant Screen, Random, Urine, Mayo Clinic Laboratories Extended Catalog
  9. Frequency of false positive amphetamine screens due to bupropion using the Syva EMIT II immunoassay, Journal of Medical Toxicology (2011)
  10. Solriamfetol and m-chlorophenylpiperazine cause false positive amphetamine results on urine drug screening, Journal of Analytical Toxicology (2024)
  11. Contact us - Poison Control, Poison Control (America's Poison Centers)
  12. Find help for substance abuse, USAGov

AI-verified against cited sources. Awaiting expert review. Last reviewed 2026-10-03. How we build and check these pages.

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