Determination of drug levels and the effect of diazepam on the growth of necrophagous flies of forensic importance in southeastern Brazil

Larvae of Chrysomya albiceps (Wiedemann) and Chrysomya putoria (Wiedemann) (Diptera: Calliphoridae) were reared on tissues from rabbits administered twice the lethal dosage of diazepam in order to study the effects of this drug on the development of these two species. The rabbits were given 50 mg of diazepam via ear vein infusion. From 18 to 54 h, larvae feeding on tissues containing the drug developed more rapidly than larvae from the control colony for both fly species. The time required for pupariation and adult emergence was significantly greater for colony fed on tissues from diazepam dosed rabbits than for the control ones. These differences are significant for they are large enough to alter the estimate of postmortem interval based on fly development. The presence of diazepam could be detected through gas chromatography-mass spectrometer (GC-MS) in all rabbit samples and in almost all diptera samples in this experiment.