Prolonged occurrence of cocaine in human saliva and urine after chronic use.

Cocaine was detected by immunoassay in saliva and urine of chronic cocaine addicts for 5-10 days during abstinence. Confirmation by a less sensitive but highly specific GC/MS assay of unmetabolized cocaine was successful in saliva through the first 24 h of collection and for the initial 4-5 days in urine. Cocaine saliva concentrations and subject scores for cocaine craving and depression declined during this time and correlated significantly. The presence of unmetabolized cocaine in these biofluids long after the last drug administration suggests that multiple dosing and high exposure to cocaine in man leads to accumulation in deep body compartments and subsequent slow release back into circulation and eventual excretion. The prolonged presence of cocaine in saliva and urine may have implications in testing for cocaine use and in treatment of cocaine withdrawal.