Abstract
A medicinal toxicant is sometimes the cause of consciousness disorder and shock symptoms in a patient at the site of emergency medical care. A rapid drug screening kit is used as a measure for determining the cause. INSTANT-VIEW M-I (hereinafter referred to as “INSTANT-VIEW”), which is distributed by FUJIREBIO INC. in Japan, can detect 6 types of drug or drug metabolite at the same time, namely, stimulant (METH), cannabis (THC), cocaine (COC), benzodiazepine (BZD), barbiturate (BAR) and tricyclic antidepressants (TCA). The assay kit with a one-step method is easy to use and the reaction time is short at only 7 minutes. However, the operator should pay attention because the interpretation becomes positive with linear disappearance, and the interpretation with a linear disappearance is opposite to that obtained using a general immunochromatographic assay kit. We confirmed that some drug samples have a density even more than tenfold that described in the package insert, and these could not be detected owing to the measurement detection limit using imitation urine samples, in which a standard solution is added to a healthy control urine sample. Tetracyclic antidepressants and antipsychotics as TCAs indicate a false positive result following a cross-reactive examination. It is important to understand that there is a possibility of obtaining false positive and false negative results during the interpretation of the results of immunochromatographic assay kits including INSTANT-VIEW.
