I personally know two different people who have been tested for cocaine, opiates, and THC through the cheek swab testing or under the tongue testing (saliva testing) and both have told me they used any or all of these drugs and stopped for 3 days and passed these saliva tests. This appears to be how they pass all their tests as they are required to test randomly, twice a month, and if they failed, they would be out of a job and possibly in jail for probation violation. So far they have been successful. I wouldn't recommend risking a job or going to jail trying this method but it appears to have worked for them.
