How long do cocaine stay in your system?

2 wks or more: Depending on the level of use and methods of detection...Gas chromatography detects it up to about 2 wks after ingestion, and hair sample analysis may detect it a month or more later... I certainly hope you are not using cocaine....It is a bad stuff and may have long-term medical/social/legal consequences.. Be a good citizen.. Live well/healthy, toobossy.. Good luck.

Variable: Depends on what you mean. Cocaine itself is metabolized by enzymes in our blood which break it down into inactive metabolites within minutes. The metabolic by-products, called ecgnonines (mostly benzoylecgonine) can be detected for several days after a single use, depending on how large a dose it was. Another metabolite, cocaethylene, is formed when you drink on cocaine, and that lasts 2-3 days.

About a day: But effects can linger much longer because Dopamine may be depleted by repeated use, hence the "crash".