Drug retention times vary from one person to another and depend on the dosage. Your body weight, any other medication, and a myriad of environmental factors can also affect how long the drug remains in your system.
Any illegal drug use (including synthetic cannabis) is incompatible with safe aviation and has no place in the aviation environment.
Using test data
All drug tests have a cut-off level – this is the point below at which there is not enough of the substance being tested for to be detected. It is not the maximum time the drug will affect you. These cut off levels can give an indication of maximum retention times.
*Cannabis is a drug that can build up in the body and stay detectable for longer. This extended time frame only applies to regular or heavy users.
Source: New Zealand Drug Detection Agency (NZDDA)