My client got a cocaine by GC/MS result of 2000 ng/ml. Does this mean that the donor took a large amount of the drug?
Not necessarily. The urine drug level does not correlate well with the initial dose. A positive result simply means that there has been use. Two or more serial determinations may be helpful in determining new verses prior use. Cocaine clearance is so rapid (two to four days) that this is rarely necessary.
