Given the task definition and input, reply with output. 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.

Abstract: Two cases of fatal overdose with morphine are presented. Large amounts of the drug were involved in both cases, one by oral ingestion, the other by intravenous injection. Morphine concentrations in various body fluids and tissues are compared to those in the literature.
Administration, Oral