If you receive a epidural during labor, will you test positive for barbituates and benzodiazapans? Drug screen was given after epidural was given!

No. Patient's who have an epidural for labor typically receive local anesthetic and may also receive an opioid narcotic. The exact medications depend on the patient, labor, anesthesiologist, obstetrician, and practice setting. I would not expect that you received barbiturates or benzodiazepines unless the epidural was also used for a c-section and those medications were administered after delivery.
The. The medications typically used for an epidural while in labor are anesthetics such as bupivicaine, chloroprocaine, and lidocaine. These are not in the barbituate or benzodiazepine families and would not show up on a drug test as such. Sometimes mothers are given a pain killer prior to the epidural which might show up on a drug test as an opioid, but that would have been documented in the medical record. If you have questions about the testing and whether any prescribed medications could have shown up as barbituates or benzodiazepines in the drug screening, you should call your ob/gyne doctor.