Benzodiazmecmcnt
This test checks a newborn's first stool (meconium) to see if the baby was exposed to benzodiazepine medications during pregnancy.
{"Meconium testing detects prenatal benzodiazepine exposure","Benzodiazepines are sedatives used for anxiety, sleep, or seizures","Results help doctors care for newborns who may have withdrawal symptoms","The test can detect drug exposure during the second half of pregnancy","Positive results do not mean a mother misused medications—many are prescribed"}
Key facts at a glance
- LOINC
- 29160-9
- Short code
- Benzodiaz Mec-mCnt
- Synonyms
- Benzodiaz Mec-mCnt
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test looks for benzodiazepines in a newborn's meconium—the dark green or black sticky stool that babies pass in the first few days after birth. Meconium forms during pregnancy and can hold traces of substances the mother was exposed to, including medications.
What are benzodiazepines?
Benzodiazepines are a type of prescription medication that slow down brain activity. Doctors prescribe them to treat anxiety, sleep problems, seizures, muscle spasms, or to help with sedation before medical procedures. Common examples include diazepam (Valium), lorazepam (Ativan), alprazolam (Xanax), and clonazepam (Klonopin).
Why is this test done on newborns?
Healthcare providers may order this test if they suspect a baby was exposed to benzodiazepines during pregnancy. This could be due to a mother's prescribed use, or if there are concerns about substance use. The test helps doctors identify babies who may need extra monitoring or treatment for neonatal abstinence syndrome (NAS), a condition where newborns experience withdrawal symptoms.
How is the sample collected?
The sample is collected from the baby's first stool (meconium), usually within the first 24-72 hours after birth. This is a non-invasive procedure and does not require any blood draw from the baby.
What do the results mean?
A positive result means benzodiazepines were detected in the meconium, indicating the baby was exposed to these medications during pregnancy. This does not necessarily mean the mother misused the medication—many women take benzodiazepines under a doctor's supervision for legitimate medical conditions. Healthcare providers will use this information along with clinical observations to determine if the newborn needs special care or treatment.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Frequently asked questions
Does a positive result mean the mother misused drugs?
Will the baby be sick if the test is positive?
How long do benzodiazepines stay in meconium?
Is this test required for all newborns?
Sources
- 1
- 2
- 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