Hospitals use drug tests that return false positives from poppy seed bagels, decongestants and Zantac. Yet newborns are being taken from parents based on the results.
After taking a giant hit of smoke and holding it in for as long as possible, do something strenuous, while probably feeling nauseous and if it's good for sure needing to shit. About 15 minutes in you start to come down and want another hit. Also you're too busy looking at the floor to compete.
Use crack before the competition and heroine after it. The heroine hide the crack residue and you can do it with impunity.
After taking a giant hit of smoke and holding it in for as long as possible, do something strenuous, while probably feeling nauseous and if it's good for sure needing to shit. About 15 minutes in you start to come down and want another hit. Also you're too busy looking at the floor to compete.