Addiction Research Center, IRP, NIDA, NIH, Baltimore, MD, USA

Cocaine was detected in both saliva and plasma within 5-10 min following dosing, and cocaine concentrations in both matrices peaked within 30-60 min. Cmax measures for cocaine following low doses ranged from 749-1,682 ng/mL in saliva and from 258-370 ng/mL in plasma. Cocaine Cmax measures following high doses ranged from 2,342-7,249 ng/mL in saliva and from 406-655 ng/mL in plasma. Saliva/plasma cocaine ratios were generally greater than 2 in specimens collected for up to 24 hr following dosing. Benzoylecgonine (BZE) and ecgonine methyl ester (EME) were the primary cocaine metabolites detected in saliva and plasma. EME saliva/plasma ratios were generally greater than 1, and BZE saliva/plasma ratios were typically less than 1. Cocaine and metabolites were detected in plasma and saliva for approximately 24 hr following dosing.

Pharmacological effects observed after cocaine administration included increases in heart rate, elevations in blood pressure, dilation of pupils, and increases in subject-reported "High". The duration of pharmacological effects was consistently shorter than, or similar to the time course for detection of cocaine in saliva and plasma. These findings suggest that saliva testing may provide valuable insights into the onset and duration of cocaine-induced pharmacological effects. Overall, saliva testing appears to be a useful alternative to plasma testing for cocaine.