RESUMO
Drug abusers are persistently tryieg to use masking techniques for hiding their addiction. Detection of false negative results of urine morphine test which caused by adulterants is the main goal of this study. Screening test for detecting urine morphine was done by two kinds of Immunochromatography rapid tests and the positive results confirmation done by TLC. Sodium chloride, vinegar, lemon juice, nitrite, hydrogen peroxide, and bleach, with effects on pH and gravity were checked as common adulterants in urine morphine check. This data showed that, double test performance without any increase in threshold amount of morphine [300ng/ml], have 100% sensitivity for preventing false negative results due to adulterants interference. Urine morphine test in double format, with and without increasing threshold amount of morphine, can reveal adulterants interference and prevent false negative reporting