Background: Entomotoxicology as a subset of forensic entomology can be used by analysis of carcass feeding in-sects to detecting of drugs or toxins, as well as the cause and manner of death in cases of ante-mortem drugs intoxi-cation. Morphine is one of the deacetylate metabolites of heroin. The aim of this study was to determine the presence and quantity of morphine in insects on the carcass and compare them with decomposing carcass. Methods: Field of this study was in Chalabeh District and toxicological tests were carried out at the Department of Forensic Toxicology, Legal Medicine Center, Kermanshah, Iran in 2017. Morphine was inoculated into live rabbit as experimental model at concentrations of 12.5, 25, 50mg/ml, similar to those normally encountered in human over-doses, then quality and quantity of morphine were determined in insects such as Chrysomya albiceps (as the first wave of insect succession on human cadavers) fed on carcass. Results: Quantitative assessment at larvae showed that morphine was detected in all larvae (feeding and post feeding stage) fed on tissues from carcasses administered morphine, except for post-feeding larvae from R1 which received 12.5mg/ml dosage of morphine. Conclusions: Necrophagous insects are an indicator on the scene of crime and a potential source of information about the antemortem situation. Detection of drug in insects which is actually a reflection of the cause of death is possible.
