Table 1 McCarron and Wood7 classification system for drug packets
Type 1Type 2Type 3
ConsistencyLoose powderMatted powderRock-hard paste
WrappingCondoms, toy balloonsMultilayer tubular latex
x Ray appearance
    ShapeRound or cigarOblongNot seen
    DensityRadio-opaque or radiolucentRadio-opaqueNot seen
    Gas halosNone or irregularPresent and regularNot seen
    TiesNot apparent or “rosette”Not seen
HazardOften break or leachNo reports of breaking or leaching