Ethanol and Acetaldehyde Ratio (Plasma/Serum)
This test measures the ratio of ethanol (alcohol) to acetaldehyde, a toxic byproduct of alcohol metabolism, in your blood. It helps assess recent alcohol exposure and potential liver strain.
["This ratio helps doctors check for heavy drinking and possible liver health risks from alcohol."]
Key facts at a glance
- LOINC
- 19406-8
- Short code
- Cocaethylene Ur Ql Cfm
- Synonyms
- Cocaethylene Ur Ql Cfm
- Category
- chemistry
- Sample
- urine
- Container
- Sterile urine container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- confirm
- Specimen volume
- 10 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may order this test if you’ve been drinking heavily, have symptoms like nausea, confusion, or liver problems, or if you’re undergoing treatment for alcohol use disorder. It can also be part of a broader evaluation for conditions like alcohol poisoning or liver disease.
What to Expect Before the Test
No special preparation is needed, but you may be asked to fast for a few hours before the blood draw. Avoid alcohol for at least 24 hours before testing if possible, as it can affect results.
How the Test Works
A small amount of blood is drawn from a vein in your arm. The sample is analyzed using a sensitive chemical test to measure both ethanol and acetaldehyde levels, then compared as a ratio.
Possible Results and Their Meaning
A higher ratio may suggest recent heavy drinking, while a lower ratio could indicate abstinence or metabolic differences. Your results will be interpreted by your healthcare provider in the context of your medical history and symptoms.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is particularly useful for detecting recent alcohol exposure that standard blood alcohol tests might miss. Elevated acetaldehyde levels can signal liver stress from alcohol, while a high ethanol-to-acetaldehyde ratio may indicate ongoing binge drinking. It’s not a standalone diagnostic tool but supports broader evaluations for alcohol-related health risks.
Short name
Ethanol-to-Acetaldehyde Ratio
Frequently asked questions
What does a high ratio mean?
Some medications (like acetaminophen or certain antibiotics) or certain foods (like grapefruit) may influence acetaldehyde levels, but alcohol is the primary factor. Always inform your provider about all medications or supplements you’re taking.
Your doctor will determine how often you need this test based on your medical needs, symptoms, and treatment plan. It may be part of routine monitoring if you’re recovering from alcohol use or managing liver health.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
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.
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