1 Snorting typically takes one to four days. 2  Smoking crystal meth can take anywhere from three to five days to leave your system. 3  When users use crystal meth intravenously, the drug will typically stay in their system for a minimum of 72 horus.here are several factors that alter how long it takes for the crystal meth to completely leave your system: Another factor to be considered is in regards to drug testing. Crystal meth, as with other drugs stays for different amounts of time in different areas of the system that are normally tested.