Precursor to metabolite: Halazepam to Nordiazepam

Halazepam is converted to Nordiazepam by CYP3A4.

The pair

Halazepam — Older benzodiazepine anxiolytic converted to long-acting nordiazepam; sedation, accumulation, and dependence limit use.
Nordiazepam — Long-acting active metabolite of diazepam and several other benzodiazepines; accumulation can prolong sedation.

Anything that inhibits or induces CYP3A4 shifts the balance between Halazepam and Nordiazepam.