Health Street's PEth Alcohol Test (3 week look back) looks for alcohol biomarkers that stay in the bloodstream for up to three weeks after alcohol consumption. PEth testing can detect chronic alcohol use or heavy binge drinking. This type of alcohol test is frequently used by families, courts, or clinicians that want to confirm that a person is staying sober over a certain period of time.
PEth blood alcohol testing checks the level of phosphatidylethanol in the blood. When alcohol (ethanol) is consumed, the body creates this metabolite. Even after the alcohol leaves the body, PEth stays in the person's bloodstream. Depending upon how much alcohol they drank, PEth can stay in the blood for up to three weeks. The more that's consumed, the longer this substance can be detected.
After you book and pay for the test, either by phone or online, we will send you (or the person you specify) a registration code that can be used at the clinic you have chosen. The person who is being tested can walk into the clinic and show their registration code and photo ID. Register online or call (888) 378-2499.
Below are the most commonly asked questions about this product in our call center.
This test is commonly chosen for:
It's important to note that light or infrequent drinking may not always show up on a PEth test. The detection level depends on several factors, including:
No. Health Street does not accept insurance for alcohol testing, including PEth tests. These services are paid for out of pocket.
If you need documentation for reimbursement from another organization (e.g., workplace or legal expenses), we can provide payment receipts and official test reports.
No, Health Street does not offer an at-home PEth (phosphatidylethanol) test. PEth alcohol blood testing requires a professional blood sample collection performed at a certified laboratory to ensure accuracy and reliability.
Why? PEth testing involves complex lab analysis that cannot be easily completed using a self-administered or mail-in kit. To be used for legal purposes, the blood sample must be collected by a certified professional at an accredited laboratory to ensure proper chain of custody, accuracy, and verified results.
It can take up to two weeks or longer to receive results. Once available, we'll email the results, which are signed by a Medical Review Officer. The report will indicate "positive" or "negative." If not negative, we will run a confirmation test on the same specimen, which can take additional days.
The test measures phosphatidylethanol (PEth), a compound produced when drinking alcohol occurs. This is different from standard blood alcohol concentration (BAC) test, which only measures current blood alcohol levels. PEth stays in the blood for up to three weeks, making it valuable for detecting consistent or repeated alcohol consumption, such as alcohol use disorder (AUD).
The actual blood draw for a PEth alcohol blood test is very simple and fast. Once completed, test results take at least two weeks from collection to result.
You must register online or by phone. After registration, you can walk in during clinic hours. You can find a PEth alcohol blood testing clinic near you by registering through Health Street’s nationwide network of over 10,000 licensed labs.
Initial results are usually available within 1–2 weeks. If the result is not negative, a confirmation test is run on the same specimen. This process can add several business days. Results are delivered securely via email and reviewed by a Medical Review Officer (MRO).
PEth testing is best for identifying moderate to heavy alcohol use. Light, social, or infrequent drinking might not produce detectable levels.
Yes. Health Street allows you to register another person (e.g., a family member) for PEth alcohol testing. You'll provide their name, email, and contact details when setting up the registration.
A PEth Alcohol Blood Test measures phosphatidylethanol, an alcohol-specific biomarker created in the body when drinking alcohol occurs. Even after the alcohol leaves the system, these biomarkers stay in the bloodstream long after the effects of alcohol have passed. Depending on the amount consumed, PEth can be detected for up to three weeks.
Unlike standard alcohol testing methods that check for blood alcohol level at the moment of testing, PEth testing focuses on long-term alcohol use. For example, a blood alcohol level or BAC test is commonly used by law enforcement to determine if someone exceeds the legal limit for driving or is at risk of alcohol poisoning. That type of test measures how much alcohol is present in the blood right now, offering only a short detection window.
By contrast, a PEth alcohol blood test measures biomarkers that form specifically when a person consumes alcohol. These biomarkers are not present in individuals who do not drink. PEth is produced when ethanol combines with phospholipids in red blood cells, leaving behind a measurable trace that remains for weeks.
According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA), alcohol biomarkers like PEth are valuable tools for monitoring alcohol use patterns in both clinical and legal settings. This makes PEth testing especially useful when courts, workplaces, or treatment programs need clear evidence of alcohol use history—not just current intoxication.
Alcohol testing can vary based on how far back you need to measure the level of alcohol use. It's important to choose the right test for your situation:
Health Street's drug testing services offer individuals and employers many advantages and benefits.
Health Street offers many other options for alcohol testing. If you'd like to see a comprehensive list of all alcohol tests that we offer, you can view all alcohol tests here.
If the PEth Alcohol Test (3 week look back) isn't what you need, consider trying our EtG Urine Alcohol Test.