Detailed Instructions: Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
Q: Abstract: Presented is a case where the death was attributed to the deliberate ingestion of an overdose of verapamil (V). Blood, urine, and gastric concentrations of the drug were determined by gas chromatography with nitrogen phosphorus detection (GC-NPD). Identification of norverapamil (NV) was made. A presumptive identification of o-demethylnorverapamil (DNV) was also made.
A:
Adult