Hi, plasma elimination half life of clonazepam is 30-40hrs which means it is unlikely for the drug to be
present in blood after a week of its administration but this holds true if just one dose was taken on sept 10,
prior to sept 10 drugs was not taken. In case if one is taking daily dose of clonazepam which leads to
achievement of steady state concentration (4-5 times of plasma half life of drug), in that case drug can be
detected up to one week after last dose.
Presence of liver disease also led to slow elimination of drug from body.