How long does it take to drop levels from 300ng/ml to 150ng/ml for a cocaine urine screen. ?

It's relative : Depending upon ur body mass, metabolic rate and amount of consumption. On the average, Cocaine can remain detectable in the urine for 2-5 days after stopping it. Best of luck! http://www.erowid.org/ask/ask.php?id=19. http://en.m.wikipedia.org/wiki/drug_test.

Eight Days: Benzoylecgonine can be detected in urine within four hours after Cocaine intake and remains detectable in concentrations greater than 150 ng/ml typically for up to eight days after Cocaine is used.