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Acetaminphenacurqlscn

Published: August 9, 2026Updated: August 16, 2026

This test checks your urine to see if you have been exposed to acetaminophen or phenacetin, common pain-relieving medications.

Quick summary

{"This is a simple urine test to detect acetaminophen and phenacetin exposure","The test shows whether these pain medications are present in your urine","Results are typically reported as 'detected' or 'not detected'","No special preparation is needed before providing the urine sample","Tell your doctor about any medications or supplements you are taking"}

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
33277-5
Short code
ACETPHEN-UR
Synonyms
Acetamin+Phenac Ur Ql Scn
Category
chemistry
Sample
urine
Container
Sterile polypropylene urine collection cup (50 mL capacity) with leak-resistant lid
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
0–120 years
Method
screen
CPT
80307
SNOMED
397550006
Specimen volume
Minimum 10 mL; preferred 20-30 mL
Stability
Room temperature (20-25°C): 24-48 hours; Refrigerated (2-8°C): 5-7 days; Frozen (-20°C or below): 30 days. Protect from light.
Hemolysis max
0
Lipemia max
0
Icterus max
0
TAT
4–24 hours
Order
routine

What is this test?

The Acetaminophen and Phenacetin urine screening test is a laboratory test that checks your urine sample to see if it contains traces of acetaminophen (Tylenol) or phenacetin. These are pain-relieving medications. The test uses a screening method to determine whether these substances are present or absent in your urine.

Why might I need this test?

Your healthcare provider may order this test if they suspect you have been exposed to these medications, either from taking too much acetaminophen or from historical exposure to phenacetin (a pain medication that is rarely used today). It may also be part of a broader drug screening panel.

How is the test done?

A urine sample is collected in a sterile container. You will be given instructions on how to collect a 'clean catch' sample to avoid contamination. The sample is then sent to a laboratory where it is analyzed using screening methods to detect the presence of acetaminophen and phenacetin.

What do the results mean?

Results are typically reported as either 'Detected' (positive) or 'Not Detected' (negative). A 'Detected' result means that acetaminophen or phenacetin was found in your urine. A 'Not Detected' result means these substances were not found at detectable levels. Your doctor will interpret these results in the context of your medical history and symptoms.

Are there any risks?

This test involves collecting urine, which is generally safe and has no known risks. The collection process is non-invasive and straightforward.

Reference range

Negative - No acetaminophen or phenacetin detected at the screening cutoff concentrationN/A

Specimen: urine

Collect clean-catch midstream urine specimen. Avoid contamination with toilet paper or fecal material. Patient should refrain from taking any medications or supplements containing acetaminophen for at least 24 hours prior to collection, unless monitoring is specifically ordered. Inform laboratory of any prescribed or over-the-counter medications.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Frequently asked questions

Do I need to fast before this test?
No, you do not need to fast before providing a urine sample for this test. You can eat and drink normally unless your doctor gives you specific instructions otherwise.
Can over-the-counter medications affect the results?
Yes, over-the-counter pain medications containing acetaminophen (such as Tylenol) can cause a positive result. It is important to tell your doctor about all medications, supplements, and herbal products you are taking before the test.
How long does it take to get results?
The time for results varies by laboratory, but typically results are available within a few days. Your healthcare provider will inform you when your results are ready.
What should I do if my result is positive?
If your test shows that acetaminophen or phenacetin was detected, your healthcare provider will discuss the results with you and determine if any follow-up action or treatment is needed, especially in cases of potential overdose.
  1. 1
    MedlinePlus - AcetaminophenSource
  2. 2
    Mayo Clinic - Acetaminophen (Oral Route)Source

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy