 [ Symptoms ] is regular iced tea considered one of the clear liquids that may be consumed on the day before a routine colonoscopy [ Disease ] it does not unless the test was wrong or mixed up with another specimen can happen while there are occasional false positive tests for cocaine these tend to be rare if you have used cocaine in any form like snorting it or on a cigarette your test may be positive repeat the test of course if you know in your heart that you have never had contact with cocaine you can also ask for two tests   one sent to a different lab